M-2000.

Use the search feature on this site and read all about the problems I had with my M-2000...the problems took a while to fix -BUT Mesa has lived up to their reputation and I'm enjoying the best bass tone that I've ever experienced...I also have a 400+ and it is one FANTASTIC amp with a lot of thump

 

I love my M-2000 because it has more options and is more versatile than any amp I have ever played. Two serperate channels with different modes and blending capabilites is awesome. You can get a distorted agressive sound, a classic rock tone, or even a super hi-fi tone. It's all in there. Sure, they are expensive, but they are built tough and save you money, because to get all of it's features, you'd have to buy 2 compressors, 2 preamps and a mixing system. The 400+ is also awesome (but much heavier and larger). It's more plug-and-play, if you don't need all the bells and whistles...

 

I own a 400+ and it's my current favorite amp. If I didn't have so many good amps (Eden, SWR, Ampeg), I'd definitely own an M2000. Mesa rules, IMO.

 

That Mesa 2000 thingy is my favorite amp to look at. I like the knobs, little switches, screens, and all the sonic options they represent. The control panel just SCREAMS versatility. Problem is, I couldn't get it to produce any tones that I really liked. Don't worry, I know how to diddle the knobs and flick the switches. I guess the circuitry just isn't wired for my ear. Now Eden, that's a different story. That's all.

 

If you are looking at new, check out the Mesa M-Pulse 600. I just got one, and it is the best amp I have ever owned. It is as powerful as the 2000, a little less expensive, and simple (that is my new kick… simplicity!). The 2000 has too many knobs! The 400+ is awesome, but it is huge, heavy, and fragile (with all of the tubes).

 

I think the 400+ is the best because Im a tube freak.