For the last few years, I've tried tons of braids, but I like power pro the best. I've had the same 10 lbs hi-vis yellow power pro on my favorite rod for about 4 years! That would be impossible with mono! I always use a uni to uni knot to tie on about a 6 foot length of fluorocarbon to the end for a leader. This way you get the sensitivity of braid with the low visibility of the fluoro.
On a recent trip, I out-fished my friend 4-1. We were both using braid, but he did not tie on a fluoro leader.
Btw, I have never lost a fish at the uni to uni knot.
To Rob G.'s point, I was fishing for smallies in door county last October and extra long fluoro leaders really paid off. I would retie if I got down to less than 6 feet, which was a lot because of all of the zebra mussel break offs!
Diameter matters when jigging, not so much for other techniques.