You said you were looking toward hifonics, I would honestly stick with that over memphis (personal experience reasons).
But, over hifonics I would choose autotek anyday.
I have an autotek mm1400.1d
This is the sickest amplifier I have ever owned
I believe that the 1400 watts RMS is an under exaggeration, this thing definitely is pushing out a lot more than what it's rated
better yet, it does NOT heat up
also if it ever for some reason does heat up, at a certain temp it shuts off
it's a super D class amp, of very high quality
autotek is made by the same company as hifonics along with mbquart and crunch, and most believe autotek is the highest end of them all
I've owned several autoteks in my life and they have always proven strong and reliable
very hard to break etc.
On
ebay the 1400 goes for like 280 I think
they also come in
mm1000.1d
mm2000.1d
and
mm4000.1d
^ massive
http://cgi.ebay.com/AUTOTEK-MM1400-1D-CLASS-D-1400W-SUB-AMPLIFIER-NEW-AMP_W0QQitemZ250073735628QQihZ015QQcategoryZ18797QQcmdZViewItem
I don't think this one is it, but one of the
ebay stores offers warranty on all their products for a year
(yes they do sell autoteks)