WesternAnimation Confused buildup to a really good finish (season 1)
Reboots always have to face an uphill struggle, especially after Teen Titans Go soured the experience for everyone. The episodes are extremely stand alone, and we don't even get a origin episode. Now, I enjoyed Gwen's new personality and relationship with Ben (always found her unlikeable, arrogant and a brat in the original and, unlike Ben, someone who never gets called on it) and the humor is usually not cringey, but it can make difficult to get interested in it. That said, the last episode is a immense step up, and I'd say is way better written than "Secrets", from the original series, who was very by the numbers and made Ben's actions almost useless in his own show. Plus, the suddendly more serious situation is a very effective wake up call for both the characters and the audience. I especially liked the new Vilgax, who was so thin personality-wise in the original that his only lines of dialouge could have been just "Omnitrix" and "Revenge".
WesternAnimation Decent, but. . .
I have to be honest here. I never really liked Ben 10 as a whole. Don't know why, just never got into it. The fact that it ate up Cartoon Network's schedule back in the day almost as much as Teen Titans Go does now probably didn't help. But at the same time, out of the bad reboots that the network has given its old shows (Teen Titans Go, Powerpuff Girls 2016, and this show), this is probably the. . . least bad of them. It's at least recognizable as Ben 10, and the characters' personalities, from what I understand, are mostly still there, as opposed to Teen Titans Go, where they might as well be new characters altogether. It's still more of a screwball comedy than the original series ever was, and some characters who were old favorites get left out or retconned into oblivion. But they don't go out of their way to insult fans of the old show, and on occasion they do show that they still have some of the spirit of the original series left in them. So, is it good? Objectively, I would say no. It's nowhere near the league of the networks more highly-regarded shows like Adventure Time or even The Amazing World of Gumball. I certainly wouldn't watch it on principle. But if I had to choose between this either of Cartoon Network's other reboot series, I would pick it in a heartbeat.
WesternAnimation Enjoyable but not very deep
The biggest failure of this series is the lack of any overarching plot, which makes it feel like it's composed of nothing but filler. Season 1 has "Omni-Tricked", season 2 has "Innervasion", which are very good episodes but they are still plopped into the series with little or no build-up. The episodes being half-length only adds up to this: it's hard to have complex plots or character development with only half the time available.
However, it's still fairly good. The designs are a lot less cartoony then one might think from looking at the cover art, the humor is reasonably funny, and Ben and Gwen being much kinder (and much less obnoxious) to each other is a welcome change from the original series. Adaptational changes to some of the characters might not be to everyone's taste and the new characters might seem less interesting (or too cartoony), but overall this series is pretty decent. It doesn't take itself very seriously so as long as you don't either, it's fun enough to watch.