The FL350 is the one that is worth a lot. The 250's don't seem to be worth very much. Huge difference between the two even though it wouldn't seem like it. The suspension is much better on the 350 and the 350 makes a ton more power.
As mentioned, the 250 isn't very popular and not worth very much. A nice 350 Odyssey or a Pilot is worth decent money though. Seen them on CL for $1500 and up and seen some nice ones on ebay for $2500 and up.