I can't explain how, or why, but the heavy for caliber hardcast bullets offered by Double Tap, Buffalo Bore and others including hand loaders will significantly out penetrate either FMJ or JSP. I've seen test results showing 147 gr 9mm loads with these bullets penetrating 60+ " I say 60+ because they only had 60" of gel and did not catch the bullet. You see similar things with all other cartridges using those loads. With conventional JHP or FMJ we're looking at closer to 24" of penetration, often less.
If I were carrying a 357 mag where bear were a concern I'd use 180 gr bullets minimum. A 180 or 200 gr JHP would work just fine on "average" bear. If in an area where bigger, or more aggressive bear were a possibility I'd feel a LOT better with the hotter hardcast loads.
A HP bullet that is heavy enough to still give good penetration will kill quicker. I don't think 158 gr is heavy enough at 35 caliber. When you get to really big animals, especially with smaller guns you give up on expansion and go for all the penetration you can get.