Picked this up in April
Tiger Direct had these on for 69.99 AR back in April, I picked on of these up then. Usually I stay away from Refurb, but this had the same 1 year warranty directly from Garmin that comes with the new units, so I figured it was a pretty safe buy.
I replaced a 4.3" nuvi 765T with this and I have to say this is a noticeably better GPS. I like the navigation better with split screen when highway exits are coming up showing your the map and the exit details at the same time.
Another difference is the address search. With the 765, it would ask for a city first when you enter the address, and only search that city for the street you are looking for. With the 2555 you just need to enter the street name and it will search all nearby cities for it. The search engine is a bit slower to start up because of this it seems, but it is nice when you are looking for streets in rural areas where sometimes it is not clear what city you should be using.
Probably the biggest improvement is the almost instant boot up time. With the 765, It would take a 30 seconds to 1 minute or so to boot up after plugging it in, then it needed to get a satellite lock. With the 2555, as soon as I plug it in, it comes up and starts looking for satellites immediately and I can start entering my address information right away while it is doing that. This is actually a very big improvement IMO.
If you are comparing to the 50LM, I think that only includes US maps by default, Canada not included on most of the 50LM and 40LM devices sold in the US.