Go with the F90X (N90S for Americans). And you don't need the MB-10 as the camera already runs on 4 AAs with the regular MS-8. The MB-10 would allow you to have a vertical shutter release and to use CR123s on the optional MS-11 tray, if you find one. It normally comes with the MS-10 for the same 4 AAs as used by the regular camera.
The F90X used to be sold in the UK bundled with the MB-10 in a so called "Professional" package. The F90X is a semi-professional camera with shutter speeds running up to 1/8000th, exposure compensation can be done in 1/3 and it has a fantastic metering system. Compare that with the F80 that was made for amateurs and so shutter speeds only go to 1/4000th, exposure compensation is only in 1/2 and a not so high flash sync. of only 1/125th, instead of the 1/250th of the F90X.
And, to top it all, if you find or can make the correct cable, you can connect a F90X to the computer and adjust some functions from the PC, retrieve shooting data from the camera or even shot from the PC!