Here's a little story of how even a modest BMW OEM tool kit can be helpful...
My wife was driving home from our local BMW dealer after just having the value cover gaskets replaced (for the 2nd time, but who's counting). About 2/3 of the way home (50mi one way) she sees billowing smoke coming out the back. She pulls over on a 2 lane country road just about dusk. She calls me and I jumped in the ranch truck to help her.
Even the lady who stopped to help her, pointed out that there was a lot of oil dripping from under the X5. And a quick inspection showed to to be from the rear of the valve cover on the driver's side. The mechanic had not properly installed that valve cover bolt. All it took to fix this was a flash light and a 10mm wrench.. You know, like the ones that came standard in glove compartment and the trunk tool kit of our late 70's 530i. But NOT in the tool kit of that 2001 X5
If I had been in the X5 that day, we would have had quite a bill just for the flat bed to tow it the rest of the way home.
BTW There is a lot of the US that doesn't have an authorized BMW Center just around the corner. And some places where BMW Assist does not get you any help -- at all. Think Big Bend where your cell phone is as useful as a brick.
I'll be loading a small tool kit and flash light in our new (1 day old) X5 35d TODAY. I already have 2 qts of oil I picked up at delivery.
Could/would the average modern BMW owner have diagnosed/fixed this problem. Probably not. But an X5 costs $50-60k, surely a flash light and a minimal tool kit is not to much to ask for that price.
Funf Dreisig
FWIW a flatbed cost us $150 to tow her X5 home (less than 3 miles) when the X5 was totaled.