Barefoot Shoes

Spyridon LS vs. KSO Trek Vibram FiveFingers

A comparative review of the new FiveFingers Spyridon LS trail running shoe versus the original KSO Trek FiveFingers from Vibram.

Trail Running Shoe Showdown!

With Vibram’s Spring lineup coming out soon, I thought I do a comparison of the new Spyridon LS which were recently reviewed by Leah, and one of Vibram’s older trail models, the KSO Trek (review), which shares the same tread pattern as the TrekSport and the Trek LS. Due to an unpredictable winter here in the DC region, just in the past week or so we’ve had a mix of snow, ice, rain and sunny 60 degree days which has left the local off-road trails a sloppy mess—perfect for putting these VFFs through a side by side comparison. So with camera in hand and mismatching shoes on my feet, I set off to play in the mud. Video, photos, and comparison after the jump! Prepare for an epic toe shoe journey, and watch this (3:14 – headphones for full epic effect, but not necessary): So after the above muddy romp through the woods, here are my observations:
  • The Spyridon LS has a .5mm thinner sole than the KSO Trek, which is especially apparent at the heel. This gives better ground transmission overall, but when accidentally landing with the midfoot on small rocks or pebbles, the Spyridon’s molded nylon mesh midsole works like it is suppose to for an improved “rock block” effect.
  • Another design feature incorporated into the Spyridon LS is the extra wide sole, especially at the arch of the foot. In contrast at the arch, the KSO Trek has a very narrow sole with just the fabric upper positioned to protect the soft instep of the foot from painful small pebbles. If you have high arches like I do, the KSO Trek hugs the instep like a glove while the Spyridon LS has a bit more room here. Check it out:
    On the left is the bottom of a pair of KSO Trek FiveFingers (Note: an equivalent Trek sole is used on other FiveFingers models that have “Trek” in their model name). On the right is the sole of the Spyridon LS (The same Spyridon sole is also used on the upcoming non-laced Spyridons)
  • In terms of overall grip on very soft surfaces, I feel like the Spyridon did a little better in terms of helping me get up steep hills, but I was slipping and sliding and “spinning out” quite a bit. On the other hand, using a quicker cadence to increase braking ability going downhill was very similar between the two models.
  • Wet, moss covered rocks in streams crossing are slick no matter what shoe you are using. Use caution!
  • Both of my feet ended up getting pretty soaked and muddy. (I can’t wait for the Lontra to come out!) The more breathable upper of the Spyridon LS let in water and mud more quickly around the toes, but and it wasn’t until I’d gotten home that I realized that the side of the Spyridon LS’s heel is also very breathable. Here’s a visual comparison: div class=”image_block”>
    Which foot got more wet? The Spyridon LS FiveFingers clad foot (right foot) or the KSO Trek foot (left foot)? Looks like the Spyridon LS let’s in a bit more water and debris.
    In case you are wondering, those socks are Injinji’s midweight level “no-show” cut of their Performance Series line (See our review of a similar style here). Very comfortable!
  • And finally, in my opinion, the Spyridon LS also looks a lot cooler than the KSO Trek. While I found the Dayglow Yellow of the SeeYa FiveFingers to be a bit too bright for my tastes, I love the color scheme and pattern of the Spyridon LS’s upper.
  • A note about pricing: the Spyridon LS should price at around $120 (Initial word – Confirming) whereas the kangaroo leather KSO Trek MSRP’s for $125 (leather cited because it’s the likely source of the higher cost, worse breathability, and better water-resistance).
The only complaint I’ve had with this pre-production pair is that the paint over the metatarsals has started to crack (photo) after only half a dozen runs in them. Leah has also reported this problem with her pair, as well, so it may just be normal wear and tear on the shoe. We’ll keep you updated if Vibram confirms it was addressed in production models. Overall, I’ve had a similar conclusion as Leah—the Spyridon LS is a blast to run in and are now my go-to trail running VFF.

Availability and Contest

First off, the KSO Trek has been out for over two years now, and it’s still for sale at your favorite FiveFingers retailer. But if you’re a savvy toe shoes shopper, you can find the KSO Trek on sale. For example, TravelCountry has it for $100 (all sizes in stock) or CitySports for $90 (fewer sizes). TravelCountry has the women’s KSO Trek for $100, too, (but women’s KSO Treks are full MSRP at City for some reason). Other online FiveFingers retailers likely have deals on the KSO Trek, too. As for the Spyridon LS FiveFingers, they are not yet available but will be any day now! We’ll be breaking the release on and to all email subscribers! Furthermore, we’ll be giving away a pair of Spyridon LS VFFs to one lucky email subscriber who we’ll select randomly from the list of subscribers as of the time of the release announcement. If you’re already subscribed by email to, you’re automagically entered into the giveaway; if you’re not already subscribed, you can subscribe here. What more, 10 other subscribers will be selected to receive some BirthdayShoes sticker swag goodness. Note: only one email address can be entered per person; we reserve the right to bounce obvious alias email addresses off the email list (Play fair!).

By Tim

I’m am a bicycle advocate by profession and an Ironman triathlete for fun which keeps me healthy and fit. I got into minimalist footwear during the summer of 2009 after dealing with injuries resulting from running in “normal” running shoes. Check out what’s going on in my life through photos at [url=][/url] or follow me on twitter: [url=]@TimKelleyDotNet[/url]. Get to know Tim better via [url=]his interview here[/url].

8 replies on “Spyridon LS vs. KSO Trek Vibram FiveFingers”

Thanks for this comparison. My KSO Treks’ tread is getting thin and I need to replace them. I thought the KSO Trek would be the obvious choice, but I think the Spyridon is the way to go.

On the Spyridon tread: How flexibe is it? Can you flex the toes downward at all or is it pretty rigid? I try out different types of VFF’s, but always go back to my red KSO’s for the flexibility.


Why does Vibram insist on using the paint on the top of the shoes?! It never holds up and is an eyesore. With a little rubbing alcohol and a lot of patience, I removed the paint on my Komodos and they actually look better without it. I think this would be the case for the Spys as well.

I ordered a pair of Spyridons for Tough Mudder Georgia and I’m concerned they won’t arrive in time. Regardless, I’m looking forward to them.

The paint cracking so soon is going to defeat the whole purpose of the shoe’s slick design, and will be a major turnoff for many people. Hope it get’s addressed in the production models.

Well, both the Spydiron LS and SeeYa are on the Vibram site now, complete with Add to Cart button, but no sizes are listed as available, but it seems that should change in a few days. Or hours maybe?? 🙂

Love the simple, classy look of the treks. The Spyridons… not so much. I don’t get why so many manufacturers, including vibram, think minimal needs to be synonymous with loud.

Like tires. One would not put “Slicks” on for mudding the same as one would not put “Lugs” for Tracking.=0)

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