Think there is less chance of something blowing, using QSC 5050, than Naphon HI-1400, beyond 4 ohm stereo.
Engineer who has worked on amp told me, the amp is optimum at 4 ohms stereo, and does not have inherent current handling ability (transistors, power regulators, transformer capacity), to be reliable beyond that.
my bad, rephrase, rather buy 2 naphons than any other jts amp if the pricing is the same as the ua's around £1300 each. wonder how much a used annihilator would go for though...that would be interesting??