SZ19/20 spare batteries

What do users use for a spare battery and has anyone bought a charger to charge outside the camera such as the links below.

With my Canon I used batteries made by Maximal Power and these always worked well without problem even holding charge longer than the original I had.

http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Delectronics&field-keywords=Battery+replacement+dmw-bcg10pp&rh=n%3A172282%2Ck%3ABattery+replacement+dmw-bcg10pp