So some comments on the original post question....why not .357 mag?
I received in-the-field training over 3 days by 2 professionals. 1) wildlife firearms expert that trains state folks up there that work in the field/need to be able to use firearms and 2) gentleman from Gunsite Academy in AZ with general fireamrs/tactical firearms use.
First - both were carrying 10mm. One with a 1911 chambered for 10mm and the other a Glock 20. My client has two 10mm Glocks, a 20 and a 40 (longslide). This should firstly tell you something. Over and over the shot placement is priortized and nobody really talks much about your choice in round - large hand cannons like 454 Casull certainly are what is prefered IF you can handle it and fire it accurately.
We discussed .357 and the consensus is that it doesn't have the hitting/penetrating power of a 10mm but certainly, any well placed shot(s) can put down an animal regardless with something that isn't just a plinking .22 round.
If you have to choose, you want a 12g shotgun with slugs. Handguns are a backup piece of equipement but the reality is that at times you won't have a shotgun handy depending on the type of work you are doing.
I fired ~500 rounds (180g) best I can tell from my new G20 and probably half of that in slugs through a Benalli pump 12g shotgun. I could be off as we had a lot more ammo to start and I wasn't really keeping track.
After some of the basics (especially for me as a hangun AND shotgun n00b, we did lots of drills at ranges that would approximate a bear confrontation.
I think my favorite was one where we started with our shotguns (we practiced both African and American carry) slung (African in this case), unsling, fire one shot at a target ~15 yards away (only one in the gun to simulate a jam/no-fire), it jams so click on next shot, resling (quickly!!! b/c we can't just toss it on the ground in this training scenario but clearly that's what you would do) and go to your pistol (mine was in a side holster that day) delivering 2 shots (one handed!) to the upper body of a bear target from ~5 yards (to simulate that it got closer while you dealt with your shotgun). We did timed un-holstering/fire drills, you name it. I really liked the chest rig, just a bit different on getting the gun drawn safely - have to twist your torso so it's aimed down range and have your support hand high up on your chest/out of the way. The Gunsight instructor had the same chest rig as me - by Gunfighters. All and all, a great bit of paid-for-by-work training and bonus any handgun bits for me are a business expense.
My shooting with the handgun was fine for the most part considering I'm a n00b at this, reasonable accuracy but my tigger pull is too jerky at times so those like to go low...smooth. Will continue to practice b/c I'll be back there next year. Lots to take on and will work on presentation etc. at home dry firing with some range work in the upcoming year.
Travelling with the gun was simple and I have some notes over in that thread about it. Bottom line, follow the rules (TSA, airline, and state/federal!) and don't be the guy that wants to argue and be all "weird" about it etc. - those people should just ship it or not travel by air. Tell the nice person at the check-in you need to check a firearm and it's straightforward from there. The only hitch was in Richmond we had a bit of a chat about where the ammo goes - they said in the case and to be easy, I put it there (lucky it fit!) but neither American Airlines or TSA rules say you can't just toss it in your bag in the correct packaging. On the way home from AK, it was easier but they deal with this day-in and day-out and I had more ammo coming back just in the packages in my bag with no issue. You sign a small paper form saying it's unloaded. I carried my locks in my pocket to make the process smoother once it was checked to be unloaded. You don't need TSA locks, also lots of confusion it seems on that. I just used basic Master brass pad locks and a small Pelican Vault case (one for every hole and make sure when locked you can't get your hand in it). Mags went with the gun in the case. Gun had the chamber cable lock in to make it easy to see it was unloaded. Simple. TSA never went in my bag either way to look. When you get home and if you travel like I do, go through your bag and make sure there is no loose ammo rolling around/left over...that will be a bad day if you travel internationally as can be evidenced by a recent story in the news...I'm in Brazil next week but won't be using that bag and I did have some ammo get loose b/c the box got mangled for whatever reason.
I cleaned up the Glock and oiled it. It never flinched. I used the Lucas CLP and their oil.
Nice day on the beach and the chest rig makes riding an ATV easy.