With a tune they will work alright (some say its not worth it either way), sorry for omitting that detail. I know a few evo's that are tuned, run 100% VTA and are happy with it, no problems, etc.

I run a TS BOV @ 50/50 VTA on a tune, no issue, but a lot of jerking when letting off of heavy throttle. I know its not 100%, but I have not upgraded. I like the swoosh, so I'm staying with a VTA.

If you're concerned about the effect on the ride after being 100% VTA, I cant help you there, but you need to feel confident about the car you're getting.

Good Luck