ive got the mb 2150 ive had it for like 5 months with no probs and i like it. i havnt heard anything bad about the 2150 or 4125. but i plan to get the crescendo 1000c4 next week or so though cuz i wanna get a 4 chan and more power and they are $199shipped right now. i also plan to get a pair of the crescendo 3k's so then my amps will all match