Hmm, hard for me to say, but I can say that I dislike Toto-Rak more ever since they made the change where stepping on and off of that green goo causes sound effects to happen (when the "leaden" status is applied and removed). I KNOW for a fact the goo didn't used to work that way and I will never understand why they felt changing that was a good idea. It makes the goo about 300 times more irritating to me... so if that was the point, well then, mission accomplished, I guess.

Tam Tara, toto-rak, and Vishap are the absolute worst and I get them CONSTANTLY. Once in a very blue moon I'll do a leveling roulette and get Ifrit trial and it makes me scream with joy.
Vishap is a total joke nowadays (never lost it since the nerf, even in some pretty bad parties that would have not stood a chance pre-nerf) and the trial actually gives bonus EXP compared to (all of?) the rest of the trials on the roulette.