Wheel upgrade from stock 18" to 20"

[X5guyCT]

Hi Everyone. I just picked up a 2009 X5 30i and this is my first BMW. I did do a forum search on this topic but could not find an answer to my specific question and would greatly appreciate your expert advice.
I'm looking to upgrade the stock 255/55/R18s to 20s. From what I've read on the forum, the standard upgrade appears to be the 275/40/R20. I'm wondering if there's an advantage or a disadvantage to going with a 275/45/R20 setup. The 275/45 has a slightly larger diameter over stock and about an 11% reduction in the sidewall height.
The 275/40 is just barely under stock diameter and has about a 22% reduction in the sidewall height.
I'm not interested in doing the staggered setup as I'd like the ability to rotate my tires.
I'd greatly appreciate your thoughts on whether the 275/45/20 will work on this X5 with a 20”x8.5” wheel or whether the 275/40/20 is a better option. Thanks very much!

[MIKYZZ4]

This is a BMW Forum, not Tesla?