Rather intuitive setup. It's very similar to competing products (logic, Protools.....etc)
There are lots of tutorials for studio one V2.
No incompatibilities (as far as I can tell). You need to switch to mountain lion to avoid unexpected crashes. But now everything runs smoothly.
I use it on two computers. 1 imac I5 12GB ram / OS Mountain lion.
and on a Mac book retina i7 with 8 gb Ram.
The software is pretty stable.
Good Midi management with an M audio 8X8 + RME fireface800 + 3 BCF 2000 + different hardware synths via usb....Everything works fine.
I've used it since it came out, since Presonus released the update.
I tested logic, Protools.... But Presonus seduced me. To get into a market where Pro Tools is the standard is not easy. So I made my choice to not follow the standard. And I don't regret it.
Good value for money, regular and free updates.
I recommend it highly!