I have just recieved my RB400 2x10 combo and I must say I am quite impressed. I spent about an hour playing with it in the basement and this thing has got a beautiful tone with my skyline through it. The 2 10s actually give me much better low end than I got from my backline 115. The tone is very true to the sound of the bass but has a kind of growl and punch added in, articulate clear tone thanks to the 10 inch speakers. I highly reccomend this amp. Now all I need to do is find a 4x10 cabinet to add to it, preferably one with a tweeter.