The manual says it will, but I don't know. I don't see anything on specs about GS. You can check out the manual at http://tkmavionics.com/our-products/mx300-navcomm/ [tkmavionics.com].

Also I've attached close ups of the labels on the unit. Hope this helps.
Attachments
mx300-1.jpg (217.1 KB, 20 downloads)
mx300-2.jpg (96.61 KB, 18 downloads)

N759NA - 182Q - Sophia 2
[Linked Image from visitedstatesmap.com]