I purchased two Momax 1400ah J-M1 PDA batteries direct on ebay and have been testing them for 10 days and here my conclusions.
The batteries arrived within 8 working days from Hong Kong
They were very well packaged and compete with decoder and full instructions
They are around 1.5mm thicker than original batteries, but fit snug inside the original battery cover.
Coding the batteries was quick and easy, less than 5 secs.
The batteries were tested on 188.8.131.52, 184.108.40.2067 and 220.127.116.112 with no problems, they did not work on 18.104.22.1682 or 22.214.171.1248! These are the only OS7 softwares that I tested!
The batteries took 3 full charges to reach peak, 3 days after a new software install.
The batteries have been hard booted 10 times and softbooted 15 times and have never had to be recoded.
They are giving around extra 2.5 - 3 hours of heavy use, and around 33% extra standby time.
Thank you Momax and f¥ck you R¥M
Hope this help helps