| Not sure if this is linked in to starting problems, but ....
You could ask if the bike has had ECU or Clock related problems. I think early bike could have had problems with the ECU etc. My own ECU and Clock ware swapped under warranty, these are linked and programmed to each other. I would not be put off by hearing that the ECU has been changed, but, at least you would know it has been sorted.
Not 100% sure but, I think when you hit the starter button the newer ECU takes over and will automatically turn the bike over for about 15 seconds without having to hold the starter button down. Very early bikes did not do this. Also another tell tale sign is the bottom locating pin on the back of the clocks. Early clocks have plastic locating pins, newer clocks have an ally pin with a clamp around the wiring loom plug.
My own bike get's better with more miles, first 1000 or so it stalled quite regular, next few 100 it got better and from 1400 onwards it seems fine. | 
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