I do think your enjoyment of this will hinge on your tolerance for the acting style of Zosia Mamet. If you have not seen Girls then you should know that Zosia acts in a particular style. Lots of ummms.... etc. This doesn't bother me.
The story is a bit refreshing as well. Basically a girl is about to head off to London for an extended time there (2 years or more) when she meets someone. She chooses to break it off because of that and, upon returning to New York, unknowingly rents out an apartment in the same building as her ex. Awkward hijinks ensue.
Both characters were well written and seemed like real people. Many of the situations they found themselves in did not seem unreasonable and were interesting. I particularly liked her love interest in both how he acted and how he looked as he was not the typical hollywood love interest.