Im looking to buy a gs400 type cam but i dont think they use the same batts as the 100a. I know the 953 uses the same batts but that cam is hard to find now adays. what other small 3 chip cam uses the 100a batts.
You can get a lot of really good generic batteries for the GS series on ebay. Just look for any of the DU batties, most commonly DU14 and the DU21. I know you probably have a lot of the other batteries, but this isn't a big investment if you really want to use a GS400. I have 2 DU21s from ebay and they all work. Digital conepts batteries are probably the best generic. Expect them to be somewhere around $20-$30 each.
I know your dillema. I had a 953, and wanted to upgrade to a 400 for my small camera, but the battery size was an irritation. I understand why they did it--small is better for that market--but I prefer not to have to worry about which battery I pick up. I would also love to use the DVX 5600 battery to power a consumer camera, for like 48 hours straight!
FYI, the DVC30 uses the larger battery. With the handle and hood off, it is pretty small.
EDIT: Whew, just looked at the original post date. Kinda old. Well, there ya go anyway.