I can speak from
current experience and its definitely the ugly. My Volvo
Penta 150S saildrive has only 1600 hours and has
clutch issues. Very dangerous failure mode... It would unpredictably not shift into
gear, as in reverse when approaching the
dock, for example.
To replace or
rebuild the
clutch mechanism requires removing the upper unit. This means at least sliding the engine forward or, in many cases, requires removing the entire engine to get it out of the engine compartment. This is a big and expensive job.
But the worst part is the difficulty to trouble shoot or address issues inside the unit. It's a complex clutch mechanism that can be tricky and/or expensive to repair. And if you don't want to take your chances (see paragraph 2), then a replacement unit is almost the same cost as the engine itself. As of today, a Volvo 150S is about $12,000 USD in the the US. Note, for Volvo at least, if your yard isn't a certified Volvo
Penta dealer then Volvo won't honor the warranty.
Bottom line for me is a $20K hit...

I would definitely not recommend the Volvo's at least.