I carry a rifle (.45-70 Marlin Guide gun) with me every time I go backpacking. I used to carry a dropleg holster for my Glock 20, up until a few months ago when I swapped to a .44Mag.
I now use a drop holster for a .44Mag (S&W 629). Since I have swapped over from the Glock 20, I have gone on only one backpacking trip. 22.7 miles in, 12 miles boogering around over a few days, and 22.7 miles out.
I used an Eberlestock Gunslinger (great pack, check it out at
www.eberlestock.com). Fantastic pack, which allows you to carry a longgun while backpacking. Get the M3 Operator for longer hauls (more space). I was so impressed when I discovered these packs that I became a dealer for them; now I hook up family, friends, and acquantances with great deals on a backpack that changed how I hunt, camp / backpack, and hike.
I have had zero problems with comfort carrying a drog leg holster over a normal leather belt with these backpacks. Although I think comfort is different for each person.
I have backpacked over 300 miles in the last two years with the Eberlestock packs and a drop leg holster. So, my opinion is not conjecture, but most certainly is different than Mainsail.
Try what works for you. For me, I like the safariland drop leg holsters and Eberlestock packs.
Semper Fidelis,
Kent in Utah (with some really steep and beautiful backpacking trails)