I think these old 3.0i's are great. I got my '01 a little over 2 years ago, with ~160k miles. I replaced a few items in the suspension (most urgent was the rear ball joints which were causing excessive rear camber and extreme tire wear), all the window and regulator clips. Then in year 2, the alternator died, needing a new voltage regulator, and the fuel pump died. I attribute both of those failures to just plain wear and their time was up.

Other than that, the thing is very solid. I read this list quite a lot, and from the problems I see, there is no way I would touch a V8. I value reliability much more than power. Perhaps surprisingly, the gas mileage seems to be comparable between the V8 vs. I6.

Similarly, I'd also avoid the air suspension and panoramic sunroof. Nice features, but also headaches, from what I read here.

I did some very careful ATF changes on mine (first ever on this car at 160k+ miles) and there do not seem to be any problems. I think if you do get one around 100k, and you change the ATF carefully, you'll be happy with it.

I concur with the other comment about not worrying so much about year. I'd much prefer a well maintained '01 over a less-maintained '06.

Also, I concur with the OP's comment in the first post, "There was a certain level of pride and satisfaction in fixing it."

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2001 X5 3.0i, 203k miles, AT, owned since 2014