I've been running the 402 with the otter box, it's pretty easy to use and even with the (smaller) otter box it's a little larger than say a D7 or D8. I use the SP version of Audio Technica AT831's with it. I've made some fantastic recordings with this set up but every now and then (seems to be more recently) I get some pops throughout the recording, not sure why either.
The other downfall is that the screen is incredibly bright and I havn't found a way to turn it down, so if you want to check you levels during a show that you're stealthing you have to be careful to make sure no security is around.
The Edirol R9 is almost the same size and looks like its a way better unit, you can do 24bit witch is a nice feature. I don't think I'll be using my gmini much longer for stealthing as I keep getting some weird pops, I'll go back to using my D8 probably. Or breakdown and buy the R9.