I have a PA a2400d running at 4 ohms on two soundstream picasso 15's and I must say that I am some what impressed with the amp. I am still testing sub and box designs but they pound pretty hard with my current setup. I am not one who would normally buy non main stream gear but I am glad I decided to try this amp.
Efficient is what this amp is, well at 4 ohm sure but I ran it at 1 ohm for about one week and it seemed like it may not be a current hungry amp. Yes the 15's can't take all that power and no I never got it up to full tilt at 1 ohm but I tell you the amp rocks.
Sounds just as good as any other amp I have installed, well close enough anyway... no turn on/off pops, nice feature set, low price.....I don't like the look of it but it's got power. And I know a guy who is running a strapped pair of PA a3000d at 1 ohm and has been for more then a year. But he doesn't drive them full tilt. PA will not recommend doing this but it works for my friend. I would get one and not wait.