There are some good and bad elements in this production. I have a feeling that even with the move to the Acorn, most of the staff is either unpaid or significantly under paid. The sound was awful. Microphones didn't work more often then they did work. The band was way to loud and overpowering- it should have been moved off-stage to compensate. The cast (and it is a large cast) didn't seem to be comfortable singing! Vocally, they were mostly unpolished and off-key. At times, it really did seem like a high school production. (a pretty good one for high school, but not so good for off-Broadway!). 
Now - let's get to the good part. The actors were all physically committed and engaged - and dedicated to their characters and the drama. It's a physically demanding show. I saw lots of acting talent on stage. Two rather mesmerizing boys still stick out in my head - Anthony Michael Sanford as Woof and Kai Chapman as Apache - (ah, the beauty of youth!). The leads, Ryan Stone as Berger and Logan Hall as Claude showed great promise and I look forward to seeing them both acting on Broadway stage in the future.
The show ran close to 3 hours - as they didn't cut a single number! The talented band blasted out the shows favorites - Aquarius, Let the Sun Shine In, and the title number, Hair. The costumes and props were adequate - again, with a limited budget - they seem to have pulled that part off quite well (and it wasn't so bad looking at Apache without a shirt anyway).
I read another review of this production which noted that Hair was never intended to be polished and packed with talent. True to its origins at the Public Theater in 1967, it is actually meant to be raw and counter-establishment. To the discerning Broadway viewer - that may end up being a contradiction - both visually and aurally. It's possible that this production actually hits this original mark. Food for thought.
Overall, it must be quite fun, but still challenging, to spend 3 hours pretending you are stoned out of your mind! No doubt about it - this cast had FUN on stage. And that's important too!