divine_madness said:As for alkaline vs NiMH, I might grab some NiMH batteries at some point, but the Alkalines aren't proving restrictive.
To be honest, unless you're rapidly taking photos at full flash power, it won't make much difference, especially since ETTL metering will reduce the flash power as necessary.
I went with 4 x 2300mAh batteries for my Canon speedlite 420ex. They cost £15 with a fast charger from a high-street photographic retailer. Saves money on buying (decent!) alkaline batteries.