Well, it doesn't surprise me that this is going to be somewhat divisive, but I fell very much in the love camp. Two hours of hilarity and joy with just a touch of sweet genuineness at the end. It's not deep stuff, and if you expect something more, you're going to be disappointed. Think of the Goes Wrong shows, but much less physical. Laughter is the goal here. There are some solid tunes, though, and the two guys are amazing; they're clearly having a great time together, and it radiates to the audience.
As has been mentioned, Jonathan Groff pitched up the end in a cute cameo (he was clearly having fun, too). It's hardly an earth-shattering moment, but it's a nice touch, and I imagine they could stuff all sorts of different people in, and you'd get something just a little bit unique at each performance.
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There's also a neat set reveal at the end, which probably cost way too much for how long it's seen, but it's fun and ties the optimistic ending up nicely.
Overall, I'd wager this will find an audience once word gets out, but it won't be for everyone. I give them credit for their marketing, which is entirely aligned with what the show actually is. I'd also mention I went with my tween son, and he had a blast. I wouldn't take young children, but it's family-friendly.