I need to get a GPS unit for a mtn biking stage race that I plan to do in 2013. I have read through the information on the race website and they recommend the Garmin Oregon 450 above others. So I went to REI.com and there are 2 models the Oregon 450 and the Oregon 450t.

Does anyone have any experience with these? Do you understand what the difference is between the 2 models? Is it worth another $67 to get the 450t?

TIA for any input you can give.