P-Line Spectrex for spinning, PP for casting.  I think the Spectrex has more body, and I noticed it got fewer wind knots on spinning gear, but the PP handled better on casting gear.  Also, I couldn't pick out a backlash of Spectrex for the life of me. 

Fireline braid for sure. I used power pro once and it seemed too stiff for me. Suffix would be a close second.

I have only used PP.  I use 50# on my casting rigs and the 20# on my spinning rod.  I was looking at the Sufix today to maybe try to save a buck or two, wrong!  It was $5 more for the exact same test and amount as the PP.  If I had went to Walmart rather than Academy the PP would have been $2 less than that.  It works great on both my caster and spinner, I have no reason to switch.  Also I still use good ol Trilene XT on my crankin rod, works great, no reason to look for another.

Cliff

Power Pro

I use Power Pro as well. The only other braid I have tried was fireline and was really dissappointed in how stiff it was, and knots just wouldn't hold.

Like others have stated already, it is easily available, works well, and I have no reason to change. Backlash is easily removed if it does occur. The color fades. So what?