Using gps modem with mega

Hi there,

Iv started a project using an arduino mega and a gps module. The plan is to use it to track a dog and be able control the area that they are allowed roam by setting up a gps boundary and being able to shock the animal like existing wireless collars.

Iv found this gps module:

http://www.cooking-hacks.com/shop/arduino/shields/gprs-gps-quadband-module-for-arduino-sim908

Using this module would also allow me to text the owner if the dog or any other animal went beyond the boundary.

I have to use a mega as the leonardo and uno caused too much trouble and unreliable last year.

Anyone used ever used this particular module with mega before?

its a bit pricey so would like to find out if its any good before purchasing.

Or, any suggestions for alternative modules?

Thanks