Well, My second Band 2 just died. Yes battery has been awful pretty much since I got it (3 months ago), 30 hrs at beginning, and for like the past months it was lucky to get 24 hrs.
This second Band 2 died by slowly tearing at both sides of the clasp. First one I owned three months and that one died in the same manner. This one also lasted 3 months.
My Band history:
Band 1- Oct '14 - Summer 15. Clasp Broke completely off. Great battery life though- nearly 40 hrs. Warranty Replaced
Band 1- Summer 15-December '15. Stopped working one day completely. Battery was okay- 36ish hours. Warranty Replaced.
Band 1- December 15- Sold new in box on ebay to help pay for Band 2.
Band 2- December 15-March '16. Started with great battery, matching my Band 1's. But after about 6 weeks it went to S***. 24 hrs was hard to come by plus the rubber clasp was tearing. Warranty replaced.
Band 2- March '16-Today(June '16)- Battery started okay (30ish hrs), quickly fell to 20-24 hrs.
So I'm off to local MS store, where I'm sure they'll once again make me ship it and have me wait weeks for replacement.
I like the software and the features, so I'll probably buy Band 3. But the choice of battery supplier and the material selection for this product was a huge miss. At least they have the decency to honor standard 1 year warranty.
I like to make fun of how useless my gf's apple watch is for health but at least it looks like new after 6 months of use, meanwhile here I am heading to get my third Band 2.