Mounted pvm for the first run, as that's how I normally play. While mounted, following pets still lagged half a screen behind so there wasn't much difference in the gameplay experience.
I then went back and did some pvp tests with various people and pets, both mounted and on foot (where the follow speed was definitely noticeable and was such a nice QOL improvement after dragging around slow as fuck pets forever).
My conclusion is that the speed boost is a good change even though it may seem alarming at first. For example, one of my opponents was freaking out about the pet speed as I was attacking him and yet my pets never managed to kill him until he ran out of pots.
They did have him on the run, and if that was a real scenario it might have bought me enough time to escape a pk attempt. Eventually he stopped running and was able to just stand there healing and potting through their attacks because of the lack of special attacks or interrupts.
And it was the same with every opponent, and for me when I was the target -- we only died when we ran out of pots or made a mistake such as letting ourselves get boxed in. Which means there are counters, just like with any other kind of pvp.
Perhaps the most revealing test was when I had a 120 tamer with 120 pets attack me while I was on foot with no armor, no regs, no pots and no defensive skills. Even at a severe disadvantage like that I didn't get one-shotted, I had some time to run and try to get away.
