I had the sidis as well...(not the rich man vortices, but the poor mans something or anothers) The only issue with the replaceable sole, is the inner sole is not, and when I say inner sole its the hard plastic (behind the rubber sole), not the rubber sole. Make sense? probably not...

When fat kids like me have so much weight on their pegs it actually starts to cup the plastic in, and is not reversible...I managed to punch through the sole, all the way through the plastic and padding straight into my foot during the 4 hour... its a fat kid thing... but I think I'm gonna get used Sidis again anyways. That is when I hit the sperm bank and can afford them... I like the adjustability of the sidis, fit like a glove and aren't super heavy.

A stars came flying off my foot in a wreck my novice year and felt like tube socks on a weiner...yeah just like that...not right at all eh? So I am biased, but all I have ever had since are hand me down sidis off ebay, so my advice probably shouldn't be trusted....