I have played a bunch on both idev and pc. Started on idev for my first two years, but since have split my play about 60-40 in favor of idev. PC is the surperior medium for sparring, if I would say it straight. Though facing lag and delay on a PC is basically a crapshoot. However, I think that Idev is much, much, much harder to get the hang of than pc. Not that pc is easy, but it is closer to what most people are used to. Just my thoughts on the matter.
In response to OP.
I would say that I enjoy the initial rounds of idev far more then I do mixed. Once you hit round 4 of idev or so I start to see myself gravitate to the notable mixed matchups.