But they're still a lot pricier than plain old flatbed scanners. I guess it comes down to whether you wan to control the whole process yourself and not deal with developing. Cameras that I have seen used a set of batteries in very little use. A lot of this depends on how you use the camera. Everyone switches from Alkalines to rechargeables almost immediately.
NiCads give up the ghost a lot sooner.
If it's one of the older, slower models - there won't be any difference at all. But if it's a newer, faster model like the Nikon 700 we tested - yes, you can tell a little bit of a difference. There are different degrees of JPEG compression, though, which can make the quality loss become more obvious. Look in areas of solid, dark color, for instance, and you'll often see a faint pattern of speckles resulting from heavy JPEG compression. I waited on the sidelines for a couple years as we went from VGA to X-VGA, etc.