Sean makes a lot of good points. A good amp(and we are generally speaking of solid state in this thread) will be able to drive difficult loads. A classic ss amp doubling power as impedence is halved. Usually, I would opt for the class A amp. Remember those Bedini amps of the 80s? They made some of the best solid state sound around. Class A and 25 or 50 watts, they had NO trouble driving most speakers to the desired volume, and it is truly a loss that they're not around any longer.
