Well I actually bought a container of Collinite #476 (8 oz size) this past weekend. I did this to have it on hand for the fall detailing season, both of our cars, as well as my buddy Hectour's MS3 and his wife's Scion xB will be coated with #476 before the weather changes. This will leave me with a 4 car test of this product that's said to have amazing durability and based off of what I've seen with #845, I expect it to come through for me. Our of the 4 cars, mine is going to the only one out of the elements as I've got a parking spot in our underground parking lot, the other 3 cars will be outside 24/7 and not washed on a regular basis like mine will, so I'll be focusing on my soon to be wife's ride on a week to week basis to see how it holds up, the other 2 cars I'll have to get their inputs and go from there.
As far as #915 goes, well, I"m going to save that for the spring clean-up for the spring of 2014. In addition to that, hey, I've gotta have something new to look forward to to buying over the winter monthes, in addition to the Speedy Prep towel (fine grade) and maybe some CG's sticky wheel cleaner and whatever else tickles my fancy and God knows what that's going to be over the upcoming "off season" (well, off season for us here in the midwest, LOL)