Hopefully I'm not defaming Garmin due to a lack of technical knowledge. Im new to GPS and it's entirely possible that I'm a tech idiot and that there's nothing wrong with this unit, but I believe that this thing is a serious downgrade from the 660LM. A couple of my friends have the 660lm and from what I can gather, the 350lm has one very serious flaw that is a deal breaker for me: Any custom route that has more than 29 via points gets divided into separate trips. So, a custom route with 290 via points (for example) gets divided into 10 separate trips. At the end of every 29-point trip, you have to manually launch the next trip! The 660lm doesn't have this limitation as far as I can tell - which is very important to me as I prefer a single route on long trips. Another problem I had was that deleted routes would just pop back up no matter what I tried. With the SD card removed, manually deleting from the unit itself, a master reset, deleting and reformatting the SD card, AND deleting everything from "my collection", one of the routes I had imported via the SD card slot would just reappear. It would not delete, no matter what, even with the reformatted SD card removed! And on top of all that, my unit started turning itself off and rebooting randomly. I have no idea why. Anyway, I'm sending this unit back and ordering the 660lm instead.