Definitely Super. I tried watching GT and just grew bored after a couple of episodes. Super sucked me in almost instantly, and never let me go. (There were a few rocky bumps though in the middle).

Honestly though this franchise needs to learn how to settle for consequences.

Both shows are trash through and through, but if I had to pick one I'd be the one that I actually liked comparable to Z.

Which would be GT.

I still find myself going back to that show every so often, Super on the other hand is something that now that it's done i'm never going back too. I just can't stand Super, it's the only show I felt went out of its way to waste my time.

GT has better parts than super. But Super overall.

Well, at the beginning of Z up until the androids they were doing it pretty well. Super lost it almost completely, I never felt the thrill that gave me those episodes in which Nappa was just killing every character we'd grown to love on dragon ball, or the possibility that there would be an eventual future like the one Trunks came from (Black just wasn't enough, even though I would say it was the best part of the new series)

Tournament of power was just that, watching Goku fight with strong guys, which I admit was fun, but I never bought that universes would be permanently erased 

GT tried to give consequences to the indiscriminate use of the Dragon Balls, and I think that the final arc was pretty well done all in all, but most of the series was crap. Even animation and drawing seemed worse than Z (especially in the beginning of the series) 

Dragon Ball series from best to worst:

-Dragon Ball
-Dragon Ball Z
-who cares about the rest

But I would say that at least GT tried to really move forward, in time, but also with designs etc.
Super just look like Dragon Ball Z with different hair colors...

Super is not only far better than GT, but combines the best of Dragon Ball and Z and gets rid of the rest.

Z had too much build up and filler moments and was too serious almost all of the time.
Dragon ball was more of an adventure/comedy then an action show.

Super is serious at times but knows how to be light-hearted. Super is also a decent pace (we don't want multiple episodes filled with redundant fight/dialogue scenes to have the plot line moved; every episode feels important). Honestly, if nostalgia weren't in the way, I'd probably view Super as the best dragon ball show period. I'm currently only on the black part of the show (I have always watched the English version and I refuse to start watching the Japanese version now, even if it is ahead by a ton) so please don't spoil anything, but as of this point in the show that is how I feel (and I feel like the show is improving drastically as it goes along).

This.

The only times I questioned the pace of Super was when Gok was recruiting the fighters for the tournament, I like the recap but to spend an episode each on each fighter felt a bit of a drag. But that's maybe because I was really looking forward to the tournament.

But man Super was near perfect, especially as the episodes went on, absolutely loved it. 

DB Super of course. GT's not even close.