I am the mighty OP! The 10mm in question was a EAA Match Witness. I can't speak to every EAA out there, as I know other people on TFL will tell you that theirs runs fine... But what I had happen was that 3-4 round per 10 to 15 round mag would jam the gun.
I was inexperienced then, so I can't say that I completely vetted the gun. It could have easily been the ammo. What I would guess was that the 10mm that I had my hands on was weak. And at the time, I kind of knew that the ammo could have been the problem, and probably I should have tried more types of ammunition. However, considering the sorted history of 10mm (starting out in full power loads, then quickly becoming watered down), a 10mm gun should probably be tuned to run .40 S&W style loads and full-power 10mm.
I had sent the gun back into the factory, where they claimed nothing was wrong. Sending a gun back into a factory, as you may come to learn, sucks, especially with a pistol because most companies have a policy that they must be sent as quickly as possible. So, after getting it back in a still non-functioning state, I decided to sell the gun. 10mm isn't available in most stores here and is quite expensive, and trouble shooting it just became an expensive headache.
As many people on TFL will tell you, .44 mag is significantly more powerful than 10mm. 10mm doesn't really approach centerfire rifles like even .223 in terms of energy. .44 mag gets you into .223 in terms of energy.
To me 10mm has some advantages when compared to the .44 mag, though. It is fairly controllable, when firing quickly. 10mm isn't rimmed and fits into a magazine normally, meaning you can have a 10mm 15 round double-stack pistol, but you can only have single-stack .44. A 10mm handgun, other than a revolvers, will be smaller than a .44 magnum semi-auto handgun.
But a .44 mag could be better than 10mm under some circumstances; absolutely.