#3: Sorry, i have no A650/NiMH, but you can figure them out with the OSD values (voltage on full batts -- when the low batt warn sign appears) and post them (or append them in the wikia for your camera model)...
I read all the posts on battery setting pointed to but still am not understanding where I get these voltage numbers from. Maybe they are displayed on my charger (MAHA C-9000) and I should write them down when I finish charging batteries?
Why can't they just use the amount of charge in the battery (~2700mAh in this case and zero)? Seems a lot simpler!
#4: bigger files, depends on card speed (see also Wikia Benchmarks).
I ran the benchmark with 2 different cards
Transcend 4GB SDHC Class 6 formatted FAT16 w/64k clusters
Write (RAW) = 5150kb
Write (MEM) = 5485kb
Write (64k) = 4905kb
Read (64k) = 8714kb
Transcend 1GB SD 80x formatted FAT16
Write (RAW) = 9143kb
Write (MEM) = 9452kb
Write (64k) = 7505kb
Read (64k) = 8623b
Pretty crappy performance from the SDHC Class 6 card. I thought these SDHC Class 6 cards were supposed to be really fast. I got screwed again