Gladiator is really really great for arenas, but requires some serious setup and personalization to get it to where it needs to be, especially for whatever your playstyle is. Tuanha is more or less ready to go out of the box, and performs admirably in both PVE and PVP. I have Gladiator on my warrior, which I use in Arenas, but use Tuanha for EVERYTHING else on my Warrior, and my other characters. I would say that Tuanha and Millz produce some of the best broad CRs on the market, and Gladiator is VERY good for its niche but the price tag is a bit steep for what you get.
It took me a good few hours of customization, setup, and trial and error with Gladiator, and I already had pretty good know-how in configuring CRs. But this is really the only way to get the most out of it. The payoff is worth it in the end, but again, you're going to have to do it yourself to suit your playstyle.
