Heater is nice and warm. On a cold morning, if it's sat idling in traffic, it takes 5 mins for it to blow proper heat. Yeh, once it's up to temp it's up there for good then.
I know what you are saying about the bad thermostat constantly sitting cool, but I had similar on my Mini - started taking several miles before it was properly warm. New 'stat fixed it - warms up nice and quick now.
Ok, might get a genuine Volvo one and give it a go. What I should have asked rather than "is it easy", is : "what's going to break and disable the car if I try to change it"...
