Before I purchased mine for $299, I was thinking about waiting for the 400. I Googled and many are not happy with the new model. Some sites (I checked many) said it more of a car GPS then a motorcycle. So I figured why spend a couple of hundred more and not get much, except being able to run vertical. I don't need the features of the high end Garmin, and the 400 just did not seem like a wise upgrade from the latest version out now. I want to plan routes, be able to see the screen and find a gas station, POI, and I think I get that in this version. Heck I ride a bike that is based on a 15 year old design (and a 84 BMW) basic seems to work for me, and still write out roads for my tank bag.
Google, the 400 as it out longer your get more information. I need to replace the car unit I was using, so I made the plunge, and the V5 may get cheaper too.