A lot of people rate the 850 engine over the 1150. It is supposed to be smoother, the difference in power is marginal in the real world. DIY servicing is easy on the boxer engine. Keep an eye out for leaky shaft drives.
You will find the bike reliable, but that will also depend on its history.

I agree 102% with koko the clown. Now a member sue wilkens in Wellington has one for sale that is immaculate