I use Trailblazer for encounter building...
I only use Trailblazer for faster encounter building for games I run. I have looked at the Action point system and my players are OK with it, but they have yet to apply it, and I don't want to force something they did think to use. Like IronWolf, I'm pretty satisfied with Pathfinder, and since it is still 'new' for my group, I'm not ready to tweak or houserule it and letting the Core stand on its own.
After another year, I might be interested in tweaking and then I'll probably look more closely at Trailblazer, but so far, I'm happy with Core.
One thing because my work is intended for publication, I want to be 3pp to Pathfinder, rather than a 3pp to something in between -- Trailblazer, etc. I need to work closer to the root for a wider audience for now.
GP