@mpo I co-own a 2002 Glastron GX180 with my brother in law and ski it 1/2 dozen days a year for the past 15 yrs when we are up at the family lake cabin. 150 hp 2-stroke carb outboard. The hull on these is very similar to the current GTS. (Otherwise 99% of my skiing is behind a 2004 Malibu LXi)
The GTS has a hull with a 20 degree deadrise. The GTD a bit shallower at 18 degrees. Weight of these with motor is around 2000 lb. so a good bit lighter than an onboard ski boat. assuming the weight is similar, the GTD might have slightly less wake, but depends a bit on what you are familiar with and currently skiing behind.
I generally free ski behind the GX at 22’ off and while the wake table is pretty hard, its very narrow. I’ll try to find a photo of the wake.
Between those two boats, the interior layout and decision on having windshield protection or not may be a bigger factor for you. But if you can demo one and ski, that is going to be most informative.
Skiers in this shot are @15’ off line length.