Blackhawk in 45lc
The 44mag is nice.
45lc is also quite handy. With the blackhawks, you can fire 45lc +P which is a bit easier on the wrists and followup shot than 44magnum.
454 is my FIRST choice for dealing with bears that want to deal with me.
If you are more comfortable with shot placement, but want something for fast followup, then either a S&W or Taurus 8shot .357magnum. Federal American Eagle rounds appear to be the hottest factory rounds I can find. (158gr JSP)
I have handloaded some 180gr 357 that felt like a 45lc +P. (IMHO)
Me, I like having those extra 2 shots... Cause when you need them, you need them.
But then, I don't go around pissing off bears all that often.