Thinking of selling my 4.8is

[Scott in Cincy]

Hi Gang,
I'm thinking of selling my '05 4.8is. I've had it for a couple years now, and I've come to a crossroads with it. It has 42,000 miles on it, and my wife (who is the primary driver) puts about 20,000 miles a year on a vehicle. So, here's my thinking:

Pros:
Been relatively trouble free
I know where it's been
It's in good condition (I'm anal)
It has held it's value pretty well

Cons:
Approaching end of warranty, and I can't buy a BMW one (bought it used with 5k miles on it)
The ride on the 4.8is is harsh to me now (guess I'm getting old or something)
New ones are becoming more numerous, and I'm wondering how long before the e53 is "old"

I guess I'm trying to decide if I think it's worth keeping for another couple years. I'd have to buy the warranty for it (don't feel comfy with these cars with no insurance) and I may as well buy the mtc. package. Figure I'd have to pay 4k for all of that.

So, maybe I should just try to find another lightly used SUV, keep the same payment and start over? Anybody else been through this lately? What to buy though?

Q7? (same hp as the 4.8is I have now)
M-B M-Class? (is the quality up any?)
E70? (no deals to be had here for sure)

Thanks in advance