Got tired of hemin' n hawin' about it.
Just bought everything CREE for the rear assemblies:
Turn signals, PY21W/7505,
Bimmian WTSZZY5AB
Main brakes, P21W/1156/7506,
Bimmian WTSZZY8XB
Backup, W16W/921,
eBay 30W CREE
Panic brakes, H21W,
eBay 50W CREE
I'll give the H21Ws a fitment test in the front turn signals.
If the Bimmian PY21W pan out, which I think is a good bet, I'll be selling the 2 Silver Visions I just bought for $25/pair, firm, shipped CONUS.
Get your dibs in now. They're about $20 each, so this is about 1/2 price, and you know you'll need them before long.