I think that the quality of the accuracy relationship between the barreled action and the handle we manipulate (stock, pillars, chassis, etc.) is always going to exist on a per-system basis. Rather than make a prediction that is subject to this caveat, I will say that you have to try it (the individual solution) to actually know, and that in many cases, it will be such a subjective matter that it will all boil down to a subjective judgement.
In my own instance, i will tell you that I have never fired a chassis based rifle, and that in seeing the before and after involving a factory pillar bedding upgrade, I was woefully incapable of detecting any accuracy difference whatsoever. This took place about 15 years ago, I still own the rifle, and I probably wouldn't even now be able to make that judgement call. I will say simply that in both instances, the rifle shot/shoots fabulous, probably far beyond my own personal capability.
This 'it shoots better than I can' reference is common true in many/most cases. Modern rifles, even the factory rifles, are simply that much more accurate across the board than the ones I was shooting in the 90's. This is primarily the product of an industry's responsiveness to the demands of its clientele. I firmly believe that the Savage Accu-Stock evolved in direct response, largely from this site, to the shortcomings of its predecessor.
In the end, it probably takes a significant problem in one to indicate a difference between two solutions, and that the difference will point to a malfunction, rather than a qualitative difference between the specific bedding types.
IMHO, the real question is whether any of of the systems work at all, and if they do, they will be so close in performance as to be indistinguishable without numerical gauging methods. Honestly, I think the color of the paint makes as much difference as what kind of method one uses. They either do or don't work at all, the differences are just too close to call for the average shooter.
Assume they either work or are defective, and that the important criteria for each solution will involve the other features, like the ergonomics, rather than the bedding method each employs.
I can only offer opinions here, based on my own subjective observations, and my opinions are no more definitive than those of any other individual.
Greg