this is what all the dirtbike riders use. i like mine.
So in comparing the 60 csx to the 450t there are a few notable differences mostly due to the 450t being newer but also a little more spendy.
The 450 has a slightly larger screen with a higher resolution.
The 450 has 850mb internal memory and micro sd card slot whereas the 60 csx only goes micro sd ( mind you a 64mb card is included)
The 60csx has no preloaded maps whereas the 450 has preloaded topo maps
Tilt axis 3d compass vs straight 2d comes in the 60
Generally more storage capacity (tracks and routes)
Customizable maps and full textured 3d topo.
It is about $100 more than the 60 but if you factor in the topo map as standard vs having to buy for the 60 the difference is closer to 50.
The 60 was a perfect reference point as I was initially comparing to road GPS units as that was all I knew.
Still thinking of going with the 450t I do like a few of the extra bells and whistles as well it has a little more online connectivity plus a ton of mountain biking stuff as well.
Now to find a reasonable price for one