Yeah, I had to talk myself out of some rack effects. Eventide H8000FW certainly looked temping, but ridiculously expensive, and not even that convenient to use for live playing. I couldn't even figure out how that would work with a guitar and amp setup. You can plug a guitar directly into it, but the outputs all seem to be line-level, so I don't think I could plug it into an amp from there. It could go in the effects loop, but if I wanted the processing to hit before the preamp, that wouldn't help (and the line levels don't seem to match all amps anyway, since the unit works on +4db, but a lot of amps use -10db).
I don't even see how such an effect would be that useful in the studio, since you can only have two different effects going at once at the most. So you can't just have 16 tracks with different reverbs and delays all going - you'd have to record versions of all the tracks with the effects, then see how the mix is working after each track, and if you want to go back and change one, you'd have to start all over with it. Unless you have a bunch of these machines, I guess - then you could adjust everything in real time.
Plug-ins seem far more flexible and convenient this way, and I actually got curious as to how this was actually done in studios in the days when only rack hardware effects existed, but I couldn't seem to find anything written about it.