I have been using the Proline 3000 for a while now, 4 ohm stereo into two cubo15s per channel.
It is very good on medium power, the sound quality is great and it impresses every time. I never let it reach the clip lights however when nearing 0db, 1-2db down the sound quality does degrade slightly, it doesn't matter though, it is still good and when it gets to that point it outputs a lot of power.
it is really heavy as well, a two man lift up stairs and I have to take it out of my amp rack to take it anywhere. It is definitely worth it though.
It would probably be a good idea to buy a separate 3u case to carry this amplifier around in.