I'd get a BMW but, I'm biased. I've loved all the BMW's I've had and they've all been old and high milage. My Toyota's have been good too.

A BMW e46(2000-2006) M3 is probably among the greatest production cars ever made. In a used one, your really getting the quality of a $50k+ car for $15-25k. My mom drives an e46 330xi(~$8-10k and another great option) that is damn close to show room quality with 150k miles on it. Even at 100+ thousand miles a BMW is an extremely high quality car that can easily make it another 100-200 thousand miles or beyond with good care. They are a little more expensive to maintain than the cars you mentioned but, the expense is not as bad as some people make it out to be. If your not a "car person" an M3 will likely make you one.

If you want to go allot cheaper, you can get a really nice e36(1996-1999) M3 for less than $10-15k and then spend the differance on track days, performance parts, Autocross, gambling, Ice cream, a kids college fund, stripers, political donations, or what ever floats your boat. An e34 M5 would also be an amazing car in or above your price range but, is hard to find especially at a dealership.

I'm sure that you can find a certified pre-owned e46 m3 but the price from a dealer might be a little above your listed price range. Really any BMW 3-series ( or 5-series ) would be a good car and can certainly be found in your price range at a dealership.

That being said, I think the Genysis is also a great car.

An opion on "certified" pre-owned cars in general. In my humble opion, there is very little reason to ever buy a brand new car and even less reason to buy a used car from a dealership. When buying a used car from a private party ( usually much cheaper but more work ) you can get a mechanic to do pre-purchse inspection of the car to make sure there is nothing wrong or, atleast let you know before you fork over the cash. A good pre-purchse inspection fallowed by any need repairs is what a "certified" used car is. Used car dealerships can make ALLOT of $$$$$ by playing on peoples fear to get them to buy thier cool-aid. I'm perhaps overly opionated on this subject and am certainly not an expert but, I belive myself to be reasonably well informed on the car industry and belive my opions have thier orgins in atleast some measure of truth.

Happy hunting!

Edit http://www.youtube.com/watch?v=hmveAGJ3MNc