1. Easier clean up, less time in the tumbler.
2. Easier to police up brass after shooting, especially at a match. "No that's not mine, mine are nickel." It also shows up better on the ground.
There are no differences in loading data for brass or nickel cases. As far as I can find out, the only company making nickle cases for sale as components is Remington. These are +P cases and I have had good luck with them.
I agree with johniebravo- if you're going to have cases split, the nickle ones will usually go first, especially if they've been wet. This observation on my part is based primarily on 38 brass, since I load about 20k per year, but does apply to 45 as well. The nickle cases also scratch easier, dents look funny after they're ironed out, and can surely damage conventional steel dies by flaking (but who in their right mind uses conventional dies?). I also beg to differ that they are always easier to find on the ground. In my neck of the woods, range surfaces are grey gravel, and they blend into that surface far too well.
That having been said, I'll also confess to using them right along with the brass cases, and shooting them (unless they split) until the headstamp in unreadable!
ASR, I would recomend Walking Point advice. Save them for matches, once maybe two times fired. Since nickel is harder than brass, when it gets old it will scratch your barrel and dies(if chiped or started to peel) my two cents
I have always thought that nickel cases were to enhance removal from the chamber after firing and to give better reliability to a hand gun. Nickel is smoother than brass and slides out of the chamber easier. Thats why it is the preferred case for LEO's and +P ammos.
I won't be lied to, be insulted, or have hands laid on me, I don't do these things to others, and I expect the same from them.