Re: Anyone start on an F4i or RR?
If you've got a solid head on your shoulders and will respect the bike, the F4i would be a great choice. It is more comfortable and a bit more forgiving than the 600RR, yet will still be a bike that can provide you enjoyment for years.
Ask yourself what you will be doing with the bike. If the answer is complete street riding - commuting, canyon rides, sport touring, etc. than the answer is F4i, no doubt. If the answer is that you want to head to the track with schools, open track days, maybe even a race or two with some street riding thrown in, than the 600RR is the better bet.
The 600RR is nowhere near as comfortable a bike to ride in that the riding position is more racy, the seat is hard - not just harder, hard - etc.
The F4i is still a very capable bike, yet offers comfort and is more forgiving for new riders.
Oh, and you should be able to find clean used ones cheaper than 600RRs.