yes I have 3 Hifonic amps. 2 bass and 1 4 channel. they are ok quality, I have never had any problems with them. I did swap out my 1205 D Brutus for a Diamond audio D3 1000.1, the Diamond Audio is for sure the better amp in my opinion.
The 150.4 i have don't seem that loud but then my spearkers are acting up i got some new componets i want to install.But if it sounds the same i'm going back to my fosgate p450.4