The 5906 would be an excellent choice for the purpose you described. The 5906, in my experience, is somewhat heavy for carry but also has low felt recoil & muzzle flip which translates into very fast and steady shooting. The 5906 is as accurate and reliable as any 3rd Gen S&W auto and more capable than most shooters are. If you are looking for top tier accuracy and performance (and have the $) you might want to look at the Super 9 (there are 2 for sale in the classifieds). The Super 9 is a 5" barrel enhanced 5906. But no matter which 3rd Gen you choose, I am sure you will be happy with it.
By the way, I use the MecGar 17 round flush fit mags in all my 59XX series and have never had a single malfunction or other issue. They are, in my opinion, slightly better than the factory mags. 18 rounds at the ready makes an already great gun just a little better.