I had problems with the 3.15 stable release, so I use the latest dev build for iPod G4 monochrome. It is a bit better now, more stable, no screen glitches. I have a 32GB CF card, and a new battery in it. I assumed to have about 2 times better battery life as with the original fw, because I have an iPod Mini G2, and the battery time approximately doubled after HDD to CF conversion. With iPod 4G, the playtime is almost 11 hours(10:54:39 with CF card), tested with the built in battery benchmark. This result is lower than the advertised with the original firmware. I guess it is not that optimized as for the Mini G2. The battery is discharging a from 4,084V to 3,321V.