What about the shape and size of the models? Remember that the 6000l is huge, not exactly a slim, elegant beast. The C series tend to be small, at least from what I've seen. Which can you picture yourself using most? If you don't mind paying the extra, and the idea of pulling this huge handheld and hefting it around (a bit of an exxaguration, but not much. ) doesn't bother you at all, then the 6000l is a possibility, whereas I don't want one for precisely that reason. If you'd prefer the clamshell design, then go that route. For most, at least from what I can guess, the 5x00 is merely the first one they get.