The VX-7R is a good radio, but not as good as the considerably cheaper single-band 2m FM Yaesu VX-110. Battery life - it will easily do an hour or two on 2.5 watts (probably more), but can be supplied from a SLAB if needed. The RD on these Yaesu handhelds are not brilliant. You can buy bigger better ones to put on, but of course you would then lose the waterproof property of the VX-7R (if the rain was severe and horizontal!).
2m and 70cm with the RD are fine on the VX-7R, but 6m, even with the supplied attachment is pathetic. The extra bits and bobs like the the FM broadcast band coverage, the airband, MW (for the footy scores on BBC Radio 5 Live, used to have this on during lunch stops on the Pennine Way) and SW broadcast bands are entertaining novelties, but at the end of the day just that - novelties. I would go for the rugged tough black VX-110 2m FM handheld every time, for around half the cost of a VX-7R.
When the 817 was poorly in hospital for a few weeks recently, Jimmy and I had a major LD SOTA trip planned. We connected the HHs to the SOTA Beam courtesy of a BNC to SMA adaptor, and powered them with the SLAB (we had a few days’ multi-summit activating planned). Some summits where we could get away with it, we just used the handhelds as they were - own battery and RD, and this saved time for traverses between summits. This all worked well.
Yes, as you would expect, I would advise the 817 overall. Don’t worry about the HF. It’s the best portable VHF radio you can get for that price anyway. It is a brilliant 2m multimode, even without all the other bands. Remember, I was a class B for a while, and then after being permitted onto HF had no interest it (before CW), but the 817 was always a superb 2m radio for SOTA.
Our normal set-up is to take the 817, beam and SLAB in rucsacs ready for summit use, and carry handhelds on our waist belts for the ascents/descents.
Hope this is of use Ian. GL.