c250v1 - surprisingly good Rockbox experience!
I just now received one of the super-cheap, free-shipping refurbished/recertified 2GB c250's, with the first plan in my mind being to Rockbox it immediately upon arrival.
I did so and, surprisingly, I'm having a much better time with it than either of my Rockboxed e200 players! (The last time I Rockboxed anything before that was an Archos JBR v2, which should give you an idea how long it's been.) The c250 has very rapid startup (in either firmware) and buttons that are a bit easier to use than the e200 players'. It also responds in an intelligent and very quick way when the USB cable is connected while it's in Rockbox - it quickly switches over to the original firmware so that the USB will actually work.
I haven't tried the photo or video functions yet - the screen is kind of silly and small for that IMHO - and I'm also wondering, did I actually see this player charging in Rockbox when connected to a USB cable and wall adapter? (I know the e200's don't do that because there was some worry about just the right way to charge a Li-poly battery.)
The Rockbox install was fast and painless with the official Rockbox installer in my experience. Next to discovering the Clip's awesome sound quality (again with a cheapy refurb), this is the best time I've had with a Sansa player yet!