More battery energy capacity = larger battery volume => larger, heavier device
Or same battery capacity, longer run time = slower CPU (and already people whine about the slowness).
Sure updated battery technology (ie. Chemistry) might grab a few more mWh of capacity in the same volume of battery, but Li-ion is already near enough the leading edge.
On another note, battery life should be way better than it is to start with for these types of devices :/
More is of course always better but with 2 sensors, backlight 10% & off after 15s, follow course but "turn guidence off" (but use tcx course points for distance to next etc), map screen and data screen displayed 50/50 and NO phone pairing I can do a 200km ride taking 12 hours elapsed and still have 40% left at end, so assuming drain remains linear a theoretical 20 hours max, pretty happy with that, my 520 is 12 months old. Using a very small, weigh almost nothing external battery I can get days of continuous riding....
PS still on FW 9 as 10, 11 don't have anything for me
