read this.
http://powerstrokearmy.com/forums/showthread.php?t=3506 there is some techincal info that might be over your head, but there is some talk about the 200%, and why they prefer them over any other nozzle, hands down. im not trying to steer you to a 200%, im just saying its a good read.
and there are some of the most knowledgeable ppl on 7.3's in that thread.
if your tuner cannot tune the injector nozzle combination you decide on to be smoke free, and drive nice with low egt's, you need a new tuner. period. end of story.
that bein said, you should call a injector builder, and just talk to them for a bit. tell them what your goals are, and what would they recommend. and then call your tuner and ask the same questions. because what i want for my truck and what you want for your truck if we have the same "goals" is gonna be different.
that said, dont be intimidated about getting large injectors. just cause you have 400 cc's of fuel, doesnt mean your goin to use 400 cc's of fuel. your tuner can control the fuel you use. BUT, if your tuner says your only goin to be using, say 200 cc's, why would you get 400's? less you plan on goin big in the future.
my recommendation would be talk to your tuner and a injector builder(s), narrow your choices down to a few injectors that they feel would specifically fit YOUR EXACT needs, then ask what everyone thinks about _____ or _____ or _____. if you go that way, instead of everyone giving a opinion, you sorting through all of it, probably more confused than you started, you get it narrowed down to the ones who have tried the ones your thinking about, and get some specific info. i would have done this instead, or i love it and would do it again, i should have gotten this turbo, i wish i would have gotten this nozzle instead....and so on.