I've never ran that Potvin grind, but with a stroker motor (like 260+ inches), I'd rather see you run a Potvin 3/8. It is a beautiful grind, had a nice nasty sound and really runs well. The grind you showed was a bit mild in my opinion - but I like nasty cams!
If you want the real flathead sound and some great performance, go for the Potvin 3/8. If you need one, have Pete1 grind you one off of a stock billet. Pete and I go back a ways, he's part of the FlatCad Bonneville team and his work is second to none - you'll be extremely happy that you followed my advice!
FYI: The Potvin 3/8 lifts as noted - .375 . . . some of the Edmunds heads have small chambers and they've been milled too many times. Always CLAY the heads with a gasket - to understand exactly how much valve to head clearance you have (with any performance cam). Edmunds was not known for high valve reliefs or large chambers - he was much more like Eddie Meyer - small and traditional!
If you need more infor, just PM me.
B&S