Soundstream TN family of amplifiers have the same board as PPI Phantom Class D amplifiers. The black PPI Phantom amps have been out for a while and had become a sort of class leader among "budget amps" (amps sold for $200-230, there is even a 600watt 2-channel you can buy for like $150). The 4-channel version was reviewed by pasmag and confirmed to provide the rated power. I can imagine that given this a budget product, there could be a one off DOA amp now and then, but I don't think there have been many complaints about them. These are probably not the most sophisticated and impecable, but for the money I can't complain. The thing I like most is that they run so cool. If I put a gym bag next to my MB Quart REF4 (class A/B) amplifier, it may as well overheat and shutdown even though it runs at 4ohms and two channels are powering Hybrid Audio Imagine tweeters, that can run on 5 watts of power. The PPI having practically no air flow around it, never gets hot (granted, I only use half of the rated power).