I haven't had a formal fitting, but I do believe it's worth it to someone unsure of his gun fit. While I'll acknowledge that the stock comb profile (width, radius, etc.) has an effect that translates to effective changes in cast, knowing your dimensions for fit still gets you so close, even with this variable, that there is a big benefit compared to not having a clue. Admittedly, the very experienced shooter, that has shot many different guns with many different dimensions, may not benefit much from a fitting.