Thanks for all the feedback! I really appreciate it, guys. It really sounds like a .44 mag, as I thought, would be brutal in a 329 PD. That makes sense. Further, it sounds like the advantages of .44 are blunted in a 4" barrel, putting in more in 10mm territory (except for very hot loads).
So, if I want a woods/hunting gun that I will actually shoot, it sounds like a Glock 40 would be best or an all-steel .44 or up would be better. That means I doubt I will ever take a magnum handgun, short of a 10mm, backpacking.
Pond, James Pond: "Any reason why you're fixed on what seems to be a rather light weight gun in such a strong calibre?
There are heavier, more manageable guns that are still portable in the right holster: chest/shoulder rig?
Why then consider a gun that you'd probably shy away from using?"
Well, because I've taken guns backpacking and even a 28 oz gun tends to get left home for me. On the last trip I was on, my pack weight was 20+ lbs above the people I was backpacking with. They spend their money on high-end backpacking gear, not guns, so ever piece of gear they pack is lighter than mine, down to the snowshoes and even their pants. While, I will steadily upgrade my backpacking gear making it lighter, I don't want to plan to take a heavy gun. Taking some pounds of gun means putting myself at a distinct disadvantage against my peers.
Probably any gun I take backpacking would end up on a chest/shoulder rig. When backpacking, I already have too much stuff around the waist to make belt carry practical or comfortable.
So, I really wanted feedback from TFL on the experience of shooting a light-magnum. It sounds like something I don't want to own. I don't want to own something I am not proficient with AND something that would make it difficult to gain proficiency. Meaning, in terms of the caliber debate, most magnum handguns would only be used for hunting or range use, where I am not carrying 60-70 lbs already up and down hills and mountains on rough trail.
So, since I have some 9mm options, the only "better" gun would be a gun in the same weight class with more power OR a smaller gun. That's why the G40, G20, and G43 are on the list. The G43 would be lighter and smaller than anything I own. The G20/40 (preference goes to the G40 for a factor length legal hunting barrel) adds capability over 9mm, but no additional weight. I've owned a 10mm and have shot G20's so I know that 10mm is fine with me.
NOTE: I am not making huge jump from 9mm, since I have shot a lot of .357 and some 10mm. (Also plenty of .40's and .45's.) That being said, I want to be realistic about what is fun to shoot. I don't really want to own non-fun guns to shoot. 10mm's are fun. .357's are fun. Sounds like only a full-sized .44 mag would really be fun to shoot.