Hmm,Personally I wont advertise 15 minute quickies for many reasons. I only have done with a few regulars on the rare occasion because I know that they explode at the sight of a pair of boobs.
My friend had one that ended up being there for 40 mins.. he showered on arrival. He took ages to cum and then wanted a shower at the end as he smothered himself in baby oil. Took the p*ss if you ask me.