"Anyone heard SA/1s AND heard XA 30.5?"
I had a pair of SA/1's in my house for a month awhile back. They are wonderful amps, even by today's standards. I have owned the 30.5 for about 2 yrs now and have no plans to sell it. I'd recommend the 30.5 unless you like to play your system REALLY loud. If that were the case, I'd recommend getting the biggest X.5 amp you can afford.
BTW, I ran the 30.5 with my Maggie 3.6's. Worked fine. Room was 18x26x10 and the needle hardly ever wiggled (meaning leaving class A). After its 30 watts of class A, you still have another 100 (almost 200 into the Maggies) of A/B.
Another reason I like his newer XA.5 design:
The standby mode keeps the caps fully charged and draw just a few watts. When you're ready for a listen, there is still the wait (45-60 mins) til they heat up to spec but they sound good while doing so.