would you swap the 4.6is for an M car?

[c4racer]

I had been debating about swapping my S4 for an M3 and have decided against it. S4 is going to be a keeper for now. I love it too much and it is so much the perfect daily driver for me. Covers all of my needs - can carry our family of 4, dog can ride in the back when needed, enough cargo space for my music equipment or a bike, snow capable for ski trips, and quite entertaining to drive.

Recently we picked up a new 09 G37 sedan that the wife and I am sharing. She still has her Mazda Protege5 wagon to log a lot of the weekly grind miles. We both drive a lot right now - I'd say 45-50K miles between the two of us. G37 gets weekend road trip duty for family use for the most part now too, which used to be the X5.

So the X5 4.6is has now become a 3rd vehicle and a very part time driver. Sort of like my "garage queen". About the only thing it can do that the S4 cannot is carry bikes on the back plus the roof, or tow a trailer since it has a hitch. But I rarely do either of those things these days.

I have been wanting to get back into a BMW M car for awhile now. I have owned 2 - E39 M5 and E36 M3. So I am thinking about picking up another one of those or maybe even an E34 M5 as my "garage queen" secondary driver - special car instead of the X5. I would certainly miss the X5 for all it can do, but I think that could be outweighed by the extra enjoyment I would get from the M-car. Budget is somewhere in the mid to upper teens. Plenty of room for a really nice E36 M3 or E34 M5. I also can't get the E39 M5 out of my head now that you can get a pretty decent 70-80K mile car within my budget range. I still think the E39 M5 is the best highway cruiser ever built, and since I do a lot of highway driving it would be a good fit. I have always wanted to own a E34 M5 too - much more raw driving experience and still a good highway ride, although those are much more dated and getting really hard to find decent examples w/o a ton of miles.

I would certainly miss the X5 if I sold it. First of all I have always loved Estoril Blue, and I finally got a vehicle with this color and it is in perfect shape. And it really is an excellent highway cruiser in it's own right - right up there with the E39 M5 I'd say, but with more utility. And there are times when the S4 is tight on cargo space and the X5 works better. Also if the S4 is down for a repair or maint and I need to get my drumset somewhere I have options, which is nice.

So I'm torn...

Any thoughts? What would you do? Keep the X5? Or swap it for a M3 or M5?