I vote for SONAX or Optimum Power Clean for best bang for the buck. I barely get any use of SONAX or WG Uber though since Optima Power Clean (1:3) does the job most of the time though.
WGDGPS is still the greatest sealant in my collection. I like the look of WGDGPS more than 845 though. A bottle of WGDGPS can lasts for a long long long time anyway. The $30 extra is only paid once every few years. Why not go with the best one that I like!
Taping the rubber pillar or any black trims are very important. The black color will transfer to your pads (Extremely hard to impossible to be cleaned) and the trim will slowly fades in color, since it's been transferred to your pad instead!
I think I was able to remove them by using APC or Meg's interior quick detailer, just buff 'em out!!
I don't know if there's a more proper method though, let the pro jumps in and share some of their tricks/tips!
I use the large BF bag as well for my Rupes. You can get Sears bag for polisher only. and another smaller one for the pads and anything that should come with it. They're cheap enough that (less than $10 for 2 bags) if you wait for a sale.