Because I'm not in the market for either of those.

I think a wide ranging choice is good to have - I'm an enthusiats, and appreciate the benefits and appeals of, as you point out, two widely different vehicles.

However, they both in my price range, both affordable, so I'm considering both. :)

Unless you need the room go with the M3.

The Audi TT is for all intents and purposes a 2 seater though.

Another pertinent point is that we don't have any kids, or dogs, so I guess that relevant to the overall choice as well :)

Yeaaa, cars are too different! I was driven for two month with 330Ci (of course it is not M3!!!) but difference is huge!!!

If it is a vehicle just for you to drive and no need to carry kids around, I would go for the M3, but with a family definitly the X5. Go with what suites your needs, but if I had no kids M3 for me no question or hesitation. Have you considered the M5?

Now why would anyone want to do that?

As I implied above, my choice that I had to make last month was between a X5 and a 335xi. I chose the X5. I think that's a valid comparison
;)

A valid comparison would be the 3 series wagon with AWD and a X5.

I guess if I were just looking for a 60-75K car to buy, I wouldn't be considering a SUV, but that is me :)

So with that said, I guess the M3 would be the pick.

Getting a first year M3 is NOT a good idea.

My thoughts too... why have 2 sedans when you have an option to go for a more practical (utility) car right now.

Skip the M and just get a 335, it is faster than the old M and costs much less than the new M.