UC is still a diminishing abrasive, I can't really see how you can go wrong with it.
Autoglym SRP will hide swirls for a while, especially if you put a coat of wax over the top.
I have used SRP in the past, it helped things but not much. But I wonder if this could be my technique - I used it much like a wax, applying with a polishing pad with very light pressure, leaving it to dry then buffing with microfibre.