I have taken courses at Gunsite (1997, 2021, 2022) but never a long gun class. I have taken long gun at Thunder Ranch (Urban Rifle) and on the road (Jim Crews, Rob Haught, and Jim Higgenbotham).
I personally think the push pull technique is a game changer for shotgun. I don’t know if it’s part of current Gunsite doctrine or how much time they spend on it in 260.
if they teach it at gunsite I’d say just go to that. If not then I think I’d start with Symtac and then get around to Gunsite.
The value your friend will get at Gunsite is the combined experience of three teachers, which is good; working the donga, which is just flat fun; and working the shoot house, which I think is irreplaceable. I don’t know if they do FOF in 260 but that would be another major factor.