Overall, I think they're hipper than they are good. But considering how popular they are, they're clearly doing something right. People seem to genuinely like their donuts for more than just Instagram subjects, and I'd never begrudge any food business their right to make money making people happy with their product... but their stuff just isn't for me.
Firstly, I just don't love the dough and the fry job. I love raised donuts in general, but I don't like having to tear each bite off of the donut with my teeth like I'm biting into a loaf of chewy country bread. I also think the dough should be sweeter. The dough doesn't take on any noticeable crust from the fry, so there's no subtle crispy shell, which I consider the hallmark of a really good donut. It ends up being more like fairground fried dough; and there's nothing wrong with fairground fried dough, it's just not a donut.
Secondly, while the glazes and stuff are usually nicely made- the folks involved clearly have some good pastry skills- they often just overpower the mild, bready flavor of the donut itself. I know that some people eat pie for the crust and some people it for the filling- admittedly, I'm more of a crust kind of guy- but there isn't even a semblance of balance in many of the flavors I've tried. Sure, the bitterish chocolate ganache would be super delicious with some ingredients that could compliment and stand up to it, such as some solid whipped cream and sweet cake or something, but just smeared on top what amounts to a lightly sweetened, deep fried piece of chewy white bread... just doesn't do it for me.
Thirdly, the 'cleverness' in some of their varieties come across more as gimmicks than genuine improvements... for example, putting coffee in a coffee roll is certainly a clever idea, but it just makes them taste like bitter, stale coffee. (given, that one was right after they opened... maybe it's different now?)
Finally, I think they are overpriced for what you get. I'm happy to pay a premium for the toil of a skilled craftsperson, and they do clearly put more effort into their donuts than, say, Krispy Kreme... but not *that* much more. I challenge someone to go to the original Kane's in Saugus, or Donuts with a Difference in Medford, or Colonial Donuts in Taunton, or even Verna's donuts in Belmont, get some of their fine traditional donuts, then look at what percentage of the price they are compared to union square donuts... even adjusting for the additional real estate costs, are the Union square donuts that percent better? Personally, I don't think so.
But hey, they keep drawing in those customers and opening up new locations- more power to them. I wish them even more success in their venture. read more