I really enjoy this place (same owners as Baker Bots, I believe).
The ice cream is tasty and has a variety of unique flavours you won't find anywhere else. The dairy-free options are limited, but those they do have are fantastic.
I've only tried the traditional ice cream sandwich, and haven't tried the puff pastry or macaron options. But the cookies are good! And even the gluten free cookie is good (I find most aren't).
I think the half sandwich is the way to go - as someone who enjoys eating a lot of ice cream, I think the full sandwich would be too much. But maybe you're more adventurous than I am.
The obvious downside is the long lines in the summer. I think it's worth it though.