I have both and while I like the simplicity of a 2m only I prefer the independent 2 channel operation like the 8800. I have the FTM-350 for APRS. I haven't used 70cm much at all. Most wheeling is 2m.
I wouldn't buy the 8800 for just for 70cm though. Good thing is if you buy either one and decide you want the other they both hold their value and you can sell em here or mud no problemo.
See you on the trail
Couple o' FJ40's, BJ70, PZJ77, UZJ100, TDI