Just wanted to chime in about Mini vMac II for the Nexus 7! It works REALLY well, with some minor hiccups; the screen is off center and the mouse can be fidgety. It runs in full color, with sound, VERY fast.
I've had no problem running just about anything from the emulated machine, within reason. My .dsk image is running 7.5.5, and I'm using a Mac II rom. I use it to arrange .dsk images to be written to floppy and used on my real PPC. I love this App, it's awesome to have a Mac on the go, I just hope that the developer adds more features.
I wish also that there was SheepShaver or Basilisk on Android so I could do more work pertaining to my PPC, Mini vMac is powerful but there's only so much a 68k mac can do, especially emulated in this way. Still awesome to play games and whatnot though!
As for the Nexus 7, its my opinion that you buy the device so long as your expectations match that of a budget tablet; there are build and design issues that are causing some people headaches. The biggest problem seems to be the right side of the screen raising slightly out of the bezel edge, and mine does this though minimally. I really like mine though, and tethered to a phone its perfect for the cottage.