I have purchase many of these gp unit . they be excellent unit for navigation to waypoint in rough condition . I beat up my unit and they take it . a previous unit have a defective power button . I fix this by cut the seal and poke the on switch with a stylus . now this unit be not usable in the rain , but be otherwise work fine . on the specific unit I purchase from this vendor : this unit work fine , but have to major defect : 1 . the sd card be defective . it will hold some map , but randomly leave out many map , render it almost useless . I replace the sd card with one from another unit , and it work fine . 2 . the ability to find interstand exit be miss from this unit . as I have say , I own several of these unit , this be the only one with this feature miss .