I agree with the tit for tat bit, there is a sentiment that you are mad selling Leica to go anywhere else. Just do it. The M8 is a fine camera, I have one, and no doubt the XP-1 is as well. Try it and see. The worst that will happen is you could realize the M8 wasn't as bad after all, and buy back into one. Yep, you'll do some dough, somewhere, but that's part of the learning curve.
I'm running the same set of "what if's" in my head at the moment, not enjoying the R/F experience as a glasses wearer, whereas my DSLR with decent eye relief in the finder is much much easier.
Sell and see, report back with your findings/feelings.
Gary