I woudl prefer Cadence, but I am biased, I beat the crap out of mine many times, at a much higher ohm load than it is ratted, http://www.nexxon.com there are a few others I cant think of right now, but cheack out the new line up from them
It's the only place that I have found that has the new ones. I am totally about Cadence since I got my A7. I wish I could find one that did 1800w rms @ 1ohm though. (I can't go over 1800 or I will be in a different power class.)
cadence is not a huge name but has great potential and great products, I would like to run A7HC's but I need more power, and power is not affeccting my class in dbdrag or NSPL