the saz is a little better built and can ake a little more punishment the sae is not quite as forgiving however they are tanks also as long as ran with in heir specs..
I've had an SAE for about a year and a half now and i was pretty hard on it for part of that time and it held up pretty well. I don't know about the SAZ, but Jacob's amps are always under-rated and I'd assume you can't go wrong with either of them.