I've been using a Garmin Oregon 500 for a year. It works...but I pretty much hate the thing.
If the sun is direct as in directly overhead and the GPS is flat it is very visible. Trouble is that rarely happens and more often than not it is downright invisible due to the glare. Of course this only happens on routes I'm not familiar with, for some strange reason I have no visibility issues on routes I know
Go figure. Anyway, visibility is strike 1.
I will NEVER get another GPS with a touchscreen for bike use. Wet = invisible screen, wipe the water off and you get taken to some unpredictable page (the wipe is interpreted as a UI touch). It's impossible to work while moving on trail and still not very predictable on paved surfaces. Gloved fingers are just a touch too big and often lead to getting the wrong response. I use a toothpick to operate it now and that works great. Strike 2.
Other issues: on 3 occasions it has been off by .5 to 1 mile. It has crashed multiple times resulting in data loss. It eats batteries like they are free. A collective strike 3.
The best GPS I've used for bikepacking is the 60csx - great layout, tactile button feedback, reliable as can be. The HCx is a close second and probably better for racing as it's lighter and goes for over 40 hours on a set of lithiums. The newer units do have 10,000 track point limits compared to the old 500 limit, going back to those track limitations would be tough. The Delormes are looking really interesting right now!
Bottom line on the 450: run away.
