The racemaster doesn't have GPS technology in it so you should be fine. But, seriously, it's pretty large and it really doesn't offer that much that you can actively use on the cat besides the compass that the micro offers in a much tidier package. About the only thing I've ever seen as an advantage is the red backlight for use at night (not sure the new ones still have that or not).

Oh, and don't mount the Racemaster under a spin pole by inverting the mount...the solar cell will not get enough sun to keep it charged for more than a couple of days in a Tybee 500.