I've recently traded an R3 Mot + 28mm/f2.8, 50mm/f2 and 90mm/f2 for an M4-P and a couple of other bits and bobs of M-series kit.
The R3 Mot is a nice camera (for a re-engineered Minolta). What set it aside, though, were the lenses. The 28mm was a Minolta design but Leica glass and I've never seen better. The 50mm and 90mm Summicrons were also superb. However, what I really wanted was an additional M body. The R-series kit was just too heavy as an accompaniment to an M6TTL, 28/35/50 and 90 set. R-series also depreciate faster than Greek government bonds.....so I decided to get what I could for the kit I had, given that I hadn't paid top dollar for it in the first place - and it was mint.
The nicest R-series body, IMO, is the R6.2 which is light, reliable, sturdy and pretty well specified. The R8 and R9 have a better specification but I couldn't get them to sit happily in my hands (and I already have a DSLR).
If you really want R-series gear, now is the best time as there's some great kit out there for reasonable money compared to when new.