I've not used the Dropper as like you Mike I tend to only use one fly.
However the Perfection loop although a lovely neat knot and fairly easy to tie once you get the hang of it, is hit and miss depending upon the line you are using.
For example, I think I mentioned in my Fluorocarbon thread that I tested a few knots with different lines. I'd been using the Perfection loop for a while but found that it broke more than once with some lines, mainly Fluoro at around 40-60% and usually when a slightly stronger fish decided to test for the Olympic team and though it was a Mako Shark.
The Perfection loop with Hardy Copolymer 10lb was 66% average on 3 tests, but with Drennan 8lb was 92.5%, not bad at all. Except that the Lefty Kreh loop knot tied on the Hardy line was between 85-97% and with the Drennan 8lb was 101%. The Grinner loop came out the best overall, although not really a loop knot, it can be tied that way, Hardy 10lb broke at 10.1lb and Drennan 8lb broke at 9.7lb.
I hope this is useful.