REDDI's a no-brainer for bass — I run just about everything I can through it. It can take a harsh Digitech multi-effects pedal and make it sound smooth — recently, instead of using EQ to bring out some body from vocals recorded on an Avalon 737 and a U87, I reamped them through the REDDI — I was a bit dubious at first, since what's done is done, but not only did the REDDI bring out the body of a thin, breathy voice, but it added what I can only refer to as a little magic as well. The REDDI is an out-of-the-ballpark home run, if you like baseball metaphors (I don't, but I have several in surplus that I need to get rid of).
Whenever someone asks the question, "Why don't they..." the answer is invariably, "Money."
You're groovy, man.
Trumpet rock lives!