I haven't used this audio interface much because I busted one of the preamps and it always clipped. I had it serviced and have been using it more often lately. It can produce quite decent recordings provided you use good quality microphones. Lately I've been recording drums so I needed to use it. M-Audio never updated the Mac drivers which didn't allow me to use it on OSX so I switched to Windows 10 on a custom PC. I'm glad I did, because this setup is more powerful than my previous Mac setup. Update as of Dec 23, 2015: My ProjectMix is fried. The LCD screen won't show anything but squares and no letters. None of the faders or buttons work. I can't reset it or get it into test mode. The fact that this unit has been forgotten by M-Audio with no driver updates for years proves its unreliability. I will send it to have it serviced and fingers crossed, they might be able to fix it. If that doesn't happen, I will have to buy a new audio interface with 8 mic pres.
It's a legacy product from M-Audio, but it's definitely a product that they should continue updating and supporting because this thing is a beast. It's built great, the sliders have the right amount of resistance to it and along with that it is also an audio interface that connects via Firewire. I still use this control surface up till this day, and it works well especially with the motorized faders.