Specific examples of different E53's with different mileage on which people will base an opinion will abound here. Outside of those specific examples, I will share some thoughts:

You can easily stay WELL under budget with an m62 E53 and still have plenty of room to maintain or bring it up to your standards. You lose X drive in the non-facelift models. Of course, you'll have the classic NV125 38/62 (or whatever) split but it's not the same as XDrive if this is important to you. This is a solid choice as well since it's a motor you're familiar with.

You'll also be under budget on all but the most exceptional, low mileage N62 4.4's. Like anything with moving parts, these have their own set of reliability issues. They may be unique to N62's, but they're just that- unique when set against another motor's own unique issues.

I loved my '04 i6 E53. Plenty peppy and still a stunner to this beholder's eye. True across pretty much any displacement in NA cars, the i6's run a little lower on power way up in the band as compared to V8s. Some will say that the i6's are more reliable. That may be true to some, but it was not the case in my specific experience. The dealer replaced a 32k motor on my i6. Nothing major- not even a gasket has let go in my 4.8is @ 102k.

The 4.8is N62's are coming way down as well. This year someone on the board was unsuccessful selling one over $14k with ~52k miles. That's a unique example of course like I referenced above. I'd be thrilled to find $13k for mine and I just dropped $7k on it this year. Mine is a longer play across the next 6-7 years, I hope.

Like sizing technical equipment, I advise folks to look at the big options that generally stick with you: Engine, transmission, X Drive vs non, etc. You can find wheels, replace steering wheels, add running boards and other stuff. Getting some of those things is more a challenge now than it once was, but the idea persists: The E53 is the platform. The motor, transmission, and AWD options are the next biggest thing (to me).

The newest of the E53s will be 11 years old this year. Most of them already are or will be 12 years old. Like the E39, you'll need to be vigilant about what history you can find and what to expect based on that history being available or not.

Other than sitting in an E70 and finding it a place I did not wish to spend more time, I don't have experience so I can't offer any opinion.


Best of luck!

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