I know a several people (7-8) that have Volvo's and have never had a single failure! The Volvo also does not, to my knowledge have a coupler like a Merc does. That is good and bad as we Merc owners know a coupler can save your day or ruin it. The other downside to a Volvo drive is performance parts. I have not spoken to anyone in the propeller labbing business that knows how to lab the duo-prop volvo.
Someone also asked if the engines were the same, Volvo vs. Merc. The answer is yes. They share same basic long block configurations but the electronic package is different.