Well I'm 6'4" and 93kg and I fly the R22. OK, I
wear the R22.
As for spine injury, I don't have any medical proof, but I feel no more at risk that driving a car, riding a motorbike, or partaking in any other activity. I'm sure there are helicopters which will afford me more, or less, space, but in fact I'm reasonably comfortable in the '22. In an R44, with a little extra legroom, I am very comfortable. If anything I find the roof a little low in the 206, but I just cut my hair a bit shorter and stopped using gel.
None of which will stop me blowing squillions on my CPL(H)...
DBChopper