hi, I have had m150s for a litte over a year, had them sent back to rogue for upgrades, and love my amps ! I have had no problems, except for a couple of bad tubes the amps came with, which were replaced by rogue no problem. rogue is a great company ! the offer one hell of a product for the money. I have some friends that have purchased rogue amps after hearing mine. one friend and I did a shootout between a audio research hd220 amp and the new appollo monos and the rogues just killed the audio research ! It was better , much better in everyway possible. I think that the rogues offer one of the best values in the market today. just my two cents, goodluck, chris