My biggest concern in your case is that the Volvo is your daily driver, and that it's your only car. No matter how reliable it is, there will come times when it's going to be down for days on end.

I expect you've dealt with this and have alternative transportation options available. But if not, and being without a car for a period of time would be a major inconvenience... well, your call.

And of course, new cars can have similar issues, so it's hardly a reason for getting a new car. I personally think new cars are simply a waste, what with depreciation, taxes, mandatory insurance (unless you can pay cash), interest. Man, that adds up fast.

A newish-used car though? I could see that as being cost effective in certain circumstances... If you drive a lot of miles, something that gets 10mpg better does add up pretty quick.

But, if your comfortable with the car, comfortable with occasional down-time, content with the safety of the Volvo (which we all know is great, even without airbags).. then keep it. And it sounds like your significant other leans toward keeping the Volvo too. That's a huge one. And seemingly rare.

And, the energy and resources that are required to build a new car make keeping your old one on the road a very environmentally friendly option. Sure, you're not helping to employ auto workers, but you are helping to employ your local shop and trusted shade-tree guy. Which is the best thing.

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-Matt I ♥ my ♂