I've found that H335 doesn't seem to benefit from magnum primers, however, I use Winchester primers with it and Winchester doesn't make LP or SR magnum primers as they claim their standard primers are magnum level so I guess that I'm already using magnum level primers.
But I do know that TAC (ball powder) is much more consistent when using Remington 7½s, their SR magnum primers. The benefit I see is in higher velocities and better accuracy out at 400+ yds with my heavier weight bullets due to the lowered SD and ES my chrono shows.
Power Pistol, a great ball powder for my full power loads in 40s&W, 45acp, and 10mm. It really likes magnum primers producing significantly higher velocities, lower SD and ES and a corresponding increase in accuracy with magnum primers over std ones.
So, like all handloading, you need to test out your specific combination of case, primer, powder, and bullet choice in your firearm to see what works best for you.