How can anyone call them boring? Listen to Past Time. They pack several dozen minimal guitar riffs into every song on that album, and throw in a bunch of really cool asymmetric vocal harmonies. The songs never stop changing, but they never lose their momentum, and the band wrap up the whole thing in under half an hour. What's not to like?
While the previous comment amuses me, I don't think they're very much like Wild Flag at all. I like their harmonies and I think they have a really interesting style but all their songs are pretty samey. They definitely need to start trying some new stuff. I do like their new album though, but it's hard for me to rank it against their other albums because it sounds so similar to the others.
Grass Widow’s third album is an unguided tour through the halls that echo the band’s illustrious vocal rehearsals. Internal Logic (HLR Records) is self-aware of the fact that when Raven, Hannah, and Lillian sing simultaneously, they refract a note and make it envelope the room. The reserved sass they lyrically dollop is more obscured than usual by reverb, and they even emphasize this angelic aesthetic with celestial high-note backtracks and an a cappella ending on “Under the Atmosphere”. Listen here: http://getbent.fm/post/24140681435/review-grass-widow-internal-logic