I wouldn't necessarily avoid a Yanmar 6lp/Bravo3 combo. Yes, there's quite a few examples of issues (not just in RIB's), but it was a very popular/common setup, so is likely to attract more problems.
The Bravo3 leg isn't perhaps as robust as it could be to deal with the torque of the 6lp, so maybe not ideal for constant use in commercial operations, but as a leisure drive, should be fine if sensibly used.
I've had mine (a 2004 vintage) for about 18 months now without any drive issues. I did fit a drive shower as soon as I bought it, regularly change the drive oil, try to avoid launching off waves and digging in again at high revs, etc. With a few sensible precautions, I think it can be a pretty good setup, and very easy to get parts for.