Salomon spk boots +karma

The Kaos is a thinner, lighter boot than the SPK Pro.  Both have a lace-up liner which is either the same in both boots or very similar, but the SPK also has a stiffer flex (110) than the Kaos (100).  The SPK is basically like a "fully loaded" version of the Kaos, with the leather on the outside basically for style only.  The trouble is, that adds weight.  For a time, actually, Sammy was rockin the Kaos's instead of the SPKs because they were lighter.  I have a pair of Kaos's and the one thing I can definitely say about them is that they are super light.  I mean, they weight next to nothing, but still have a pretty good, stiff flex. 

So long story short, the three main differences are:
The SPK has a 110 flex, while the Kaos has a 100 flex
The SPK is heavier than the Kaos, but still pretty light
Both boots have full cushioning throughout the boot to prevent shinbang, heelbang and toe bang, but the SPK has an added toe shock absorber to prevent toebang even more

If I were you, unless you're going to be hitting huge jumps or you weigh a lot, I'd go with the Kaos.  A 100 flex is substantial, it holds my weight just fine (I weigh 135), it's uber light, and it's about 100-200 dollars cheaper than the SPK.  But definitely try them both on, walk in them, pick them up and gauge their weight, and flex them so you can decide for yourself which is best. 

Hope this helped!

wow
quality post.

I try =D

yes!

first off thanks for the post i gave you a 10

Im pretty sure there is a bit more padding in the heel of the PRO
But thats really the only diffrence.
I'd deffenetly get the KAOS over the PRO'S because,
Money.
Your just paying for the leather and extra weight,
Ohh and a stiffer flex.

They both have a 3D cushioning system, which basically gives you all-around support, comfort, and padding.  The only difference in padding in the SPK is the extra padding in the toe.  The pros use it because it's a stiffer flex, and they charge the shit out of their boots.  I said before that Sammy used the Kaos's for a while, but also keep in mind he's a really small guy, and that was when he was maybe 17 years old.  And also, they're pros.  They get their shit for free.  And Salomon wants their pros to ride their top-of-the-line gear. 

So basically, pros use it beacuse it's advertised as Salomon's best park boot, because it has a stiffer flex, because of the added toe protection, and because they can.

Exactly.  Unless you weigh a lot or are going to be throwing yourself off some huge jumps, or if you're going to be pushing your limits in the backcountry maybe (although I would not recommend either boot for backcountry so much), there's not much of a reason to get the SPK.  The Kaos is way cheaper, and it's an awesome boot.  You won't be dissatisfied with it.

Thanks for the karma everyone!