The last time I recorded in a studio I used a 40 year old Vox AC15. Close miked at the front and rear then two ambients in the recording room (4 channels all in all). I actually played the guitar from the control room as it was too loud to be in the same room with it (amazing amps those AC15s!) and feedback was a real problem. Seemed to work well for me.

I've also used the layering technique but found that the guitar sound could get a bit muddy and ill-defined as it's virtually impossible (for me at least!) to play the track exactly the same each time :D

Let us know how you get on.

Cheers

Dick