We became a US dealer 2 years ago and started with the us amps xt. They are now the RE version. I think the RE version looks better. It is shorter which means it goes under seats better. When we first started selling them the first thing I noticed was the fuse ratings, I figured being entry level they would most likely do about half what rated. I was wrong. They seem to put out close to rated power and are pretty clean doing it. The new version are more efficient on the input. I think they upped the fuse size on the 4000 but I can be 100% sure. Overall most of my customers have been very happy with them. We sell quite a few and so far have only had to send three back. We also sell Zapco, Kicker, Alpine, Planet and soon to be Treo. The XTs are as good as or better than the zapco I-force. They have plenty of balls are cheap and reliable.