yea absolutely listen to turbocad, i agree 110% with him. having built a handful of turbo and NA project cars, compression ratio is a huge player in whether your car will last and perform or die a very quick death.
Even if FI is a long way out, raising CR now will mean if you do end up going FI you will absolutely want to replace those pistons for low CR. Just more $$ a couple years out. Turbo with high CR will no longer make you wonder if you'll encounter detonation, but when. Just leave it stock so you don't have anything to worry about and if you decide to go FI years down the road (you never know if you might think up something new by that point) you can invest then.
In regards to the 3 companies you were looking at, I wouldn't completely discount GTM. They do make great products which are highly reccommended, especially for the VQ35DE. You may have better luck with communication if you go through one of their dealers.
I've been planning a heavy build for my FX that will soon be coming to motion within 2 months and I may end up going GTM or SFR for my turbo build along with a heavily built block/head. (Doing entire build all at once cuz I've saved for it for a long time :p ).
Best of luck to your build though man. Let us know what you end up doing and how it goes. If you want a stock block keep looking because I've seen deals here and there pop up for only a couple grand and even less if you don't want the tranny with it.