I'd have to say that actual Esbit fuel tops them all. It's expensive, but you sure get your moneys worth. I've tried army issue hexy tabs (esbit fuel is still hexamine, but of a slightly higher quality) and found them to burn rather quickly and leave a big mess.
Trioxane is another story. There was a time when all I could find was trioxane for my esbit and natick stoves and frankly, it doesn't even come close to matching esbit. Granted, it's much easier to light and I'm guessing that it also burns hotter, but the tablets simply don't have a burn time that's comparable to hexamine so you can't very well cook a meal on them.
Anyway, that's my two cents worth of an opinion....so obviously it's not worth very much!
"You're crazy." "Am I? Or am I so sane that you just blew your mind?!"