I used to use Liqui-Moly on my previous E39 M5 and E90 335d, and I liked them a lot. However, with my new-to-me 2015 F10 M5, I'm going to use the 5w-40 viscosity for my climate here in Central Texas, but I suggest folks to consider the BMW LL-01 approved Ravenol VollSynth Turbo, or VST, 5w-40.
The LM 2332 has a NOACK of 10, (I give LM credit for at least publishing such data though, most do not,) where the Ravenol VST has a NOACK of around 7.4. NOACK is all the more so important on DI engines running a turbocharger, let alone two of them. (Low NOACK essentially equates to less carbon buildup in your motor.) Ravenol is very transparent on their oil specs and I find that refreshing. Ravenol also consistently posts superior pour and flashpoints which I believe is a testament to the base stock they begin with.
You can buy Ravenol from their USA distributor in Wisconsin, Blauparts. Very competitive pricing and free shipping over $100 with no sales tax (yet.)
https://www.ravenol.de/en/products/u...sae-5w-40.html
https://www.ravenol.de/fileadmin/con...sentation_.pdf
https://www.ravenol.de/en/company/cleansynto.html