As everyone acknowledges that Volvos do require regular, competent matainence; I suspect that your problems with this particular car are likely due to 'deffered' care, rather than being indicative of a flawed product.

Getting a car like this back to normal operation can be a huge challenge. My IM deals with broken timing belts on these cars. Bent valves are common, ruined motors are not.

One example is not a fair sample of the breed, just because this one is a pita.

Good luck.