I have never shot a Dave Hall tuned rifle or a fully tuned SFS hw77/97-so I cannot comment with any authority.
I spent a couple of hours with a member off here this morning, comparing various hw80's 77's and a 97k.
We both agreed that there is very little to choose between the Lazaglided 77k and the V-Mached 97k-both a delight to shoot.
Keith had a 1980's fully Lazaglided HW80 in .22 which was superb-on the chrono it was only varying by 2-3 fps with Exacts from the tin