Obviously 10mm cannot reach .44 Magnum energy levels, but it's a potent cartridge that will penetrate every bone of every bear with the right load in the right gun, and therefore it is a viable option, and you will have more rounds and will be able to shoot faster. Let's not forget that with .44 Magnum, there is no guarantee of stopping the bear before it "stops" you. Many will argue that .480 Ruger/.50AE/.475 Linebaught/.454 Casull/.460 S&W/.500 S&W (take your pick) is the mininum they will trust to protect them from a large bear attack.
If I had the problem, I'd probably go for fewer shots with a more powerful cartdrige too, but I get that a high-capacity 10mm is an option as well. You can get real fast with some training, some will be able to put a lot more hurt on the target with a couple of 10mm rounds than they could with a hard to handle big bore revolver.
As for the 329PD: It's among the 3 worst handguns for me when shooting full power loads, the 360PD and the Alaskan .454 Casull being the other two. I'll gladly shoot a 3.5" 460 or 500 one-handed, but these 3 are punishment when shooting hot loads. They're nice and I'd give any one of them a home, but I'd only shoot lower powered ammo. You have to accept your limits.