I have both and have done quite a bit of testing in a M-29 & a Ruger SBHK and frankly I have not found much difference when it comes to one being more accurate than the other with loads in the 1,000 to 1,250 Velocity range. I was wondering if anyone else has tried both and what their results have been. One would think the 429244 would be noticeably better because it has a Gas Check.