Brushless washes are rubbish. For my Sapphire Black X3 (and my old Jerez Black E90 M3) I take it to a hand wash place.
My SSII M4 will be going through the soft cloth wash since you won’t really be able to tell
I’ll get a proper detail/polish at least once a year.
I used to hand wash my car myself, but too busy with other things, and just CBF.