I scored one on fleabay last year sometime for under 150, to replace my aging 2610. Couldn't be happier.
Previous owner was sharp enough to unregister it at Garmin, so when I got it I was able to register and get a free current map update! SCORE!
Didn't like some defaults, but it was a pretty quick process to get it set up like I wanted, with the "info" windows on the side instead of on top, allowing for more map space on screen.
It doesn't show up as a drive on the PC when connected like new units do, but that doesn't really matter since it's not a music player, there's no reason to dump files into it.
I did have to disable the older map in it when I installed the update, as it still tried to use it, and did some really odd routing tricks with both mapsets active. I can't delete the old maps without some fancy hacking I found (but haven't been brave enough to try) but since I have no need of more memory it's not an issue.
For me it was a real upgrade. The 2610 didn't do text-to-speech, couldn't hold enough maps with its default 128MB CF card, and was rather slow to acquire satallites if it had been on the shelf more than a few days. I don't know how you'll see it compared to the Zumo, but I thought the thing rocked!