I'm not sure I'd call Apaches "very low output"... :lol:
I put off getting them for years because I was worried that they were wimpy in some way. But I have ITs/Sultans/Apaches - and they're all in the same sort of ballpark output-wise. In fact, the Apaches seem to be the most capable of "aggressive strat" of the three.
All depends how you're using them and your amp, but (if I broke a string, for example) I would happily swap to any of the three guitars using the same amp settings and keep going.
Also, although theoretically the Apaches are for maple necks - don't let that stop anyone. I put them in a maple-neck strat originally, but now they're in a rosewood-neck strat (a CIJ "62"). That guitar has had all three sets at one time or other, and the Apaches are what makes it go... (something to do with it being a fiesta red maybe? :lol: The original "first in the UK" Hank Marvin fiesta red strat has a rosewood board...).
To the OP - as long as the strat has a reasonably "open" tone acoustically, I'd tend to go for ITs - that gives me what I feel is more versatility, grit/woody/bell-like, everything I need... all controllable from the guitar itself. I found in the CIJ 62, which is very warm sounding and not that bright, that the ITs didn't really give me the clarity I wanted when rolled off. They do it perfectly in the brighter and more resonant strat they sit in now.
Having said that, the Tim combo of MM in neck/middle with an Apache bridge does sound very tempting.
I also find myself wondering about the newer BKP strat sets - don't know much about them - how do they fit into this?