3 years ago I boxed up my man cave BD-UP5000 and replaced it with a cheap LG player after my wife tired of the firmware game of things working and not. I snapped a picture with the idea of putting it on ebay and never did. Today I was cleaning up bookmarks and jumped in here for old times sake and saw that people are still talking about this player. I did the firmware downgrade to 1.2 and then back to 1.7 to get the higher loader number and the things still works. I tried the just released blu-ray of Disneynature Bears and it played fine. Interestingly the DVD of Bears was rejected by the player but the new DVD from The Adventures of Ichabod and Mr. Toad played fine??? I contemplated putting it back into action in my living room where my kids stream movies off the NAS to my old Xbox with XBMC (better upscaling than the LG player on my DVD rips by far!) but the entertainment center is a little too cramped. I'm still on the fence about getting rid of it since it has the component video outputs given the fact that my living room Sony KV-34XBR910 does not have HDMI inputs and the XBOX will likely die one of these days. What is a fair asking price for a complete boxed working unit with remote manuals and all the firmware discs including shipping should I decide to part with it?
If I were you you I would keep it for old times sake. What if you run across an HD-DVD or two (there are still a few movies not on BD) or want to continue to have decent upscaling? This player is just about as reliable as any out there with the latest code. It even plays Twin Peaks just fine. Still only a handful of olden titles you can't play and hardly anyone cares about those movies anymore. Only one HD that I know of (Bubble); Splice rental, Superman/Batman Apocalypse, Chaplin the US release of Thir13en Ghosts and An American Carol. Some of which may play now with 1.7. Been trying to get folks to try Superman/..., Chaplin and An American Carol for ages now since 1.7 released. I have verified that 13... and the Splice Rental still don't load (the retail release of Splice is fine as well as the UK release of 13...). Seems like someone verified either Chaplin or Superman/... a while back but I can't remember.
Regarding the Disney DVD you tried to play; for some reason any release past 1.4 has issues with some of the newish Disney DVDs. It's been reported over and over, but it really is not a problem because why would you play the DVD in this player when you have the BD? Use the DVD in DVD players, computers, car etc. If you really want to be able to play them, just downgrade to 1.4. The loader code should stay the same, it only changes if you load 1.5 or 1.6 and now with 1.7 there is no reason to. There are still a few that won't play on any release (Disney DVDs) one I have ran into is the latest release of Dumbo.
You will need to check on eBay to see what they are going for. I stoked up years ago and have tons of players and parts so I haven't been watching the sales. I would hope you would be able to get at least $50 but possibly more if yours is 100% complete in the original box.