I'm gonna go against the grain a bit...
A Quick Detail is kindof the poor mans (or lazy mans)
car wash. It is really only intended to 'dust' off the car and can't really 'wash' - no one here would do a QD if there was any real grit on the ride!
So if you have a good LSP on there and you wash 'n dry properly, you really don't "need" to top with anything... but you "can".
For instance, I'm currently having a "Duragloss period". I'm liking there products AND their pricing. So my LSP right now is Duragloss TPP 105. I typically wash with ONR (love the stuff) and even though ONR leaves a nice shine, I will ocassionaly top with Duragloass Aquawax for some extra shine punch AND protection. You might have to experiment to see what, if any topper works well in your situation.
Be careful with some QD sprays - not all are created equal and in some cases they won't protect the finish very well if there's grit in the mix.