Lack of understanding & experience with proper use with the GF-1 built in flash has me a bit frustrated. Seems a bit too weak for much more than close ups, bit of a pain with determining the proper flash compensation to deal with the harshness of the direct flash and totally messing up on decent exposure when imaging extreme contrast subjects. So far have found it more or less limited to a fill in flash. Would the FL360 along with when needed a diffuser deal with my issues? On paper it's a stronger flash than the builit-in, bounce option, designed to work with the G line of Lumix cameras. B&H site notes not to use lithium batteries. Couple reviewers noted using the Energizer brand of lithium. Faster recycle times (+7sec for alkaline vs ~1sec for the lithium). Any long term negative effects of using these specific lithium battery.