I have the Canon PowerShot A95.
The main thing I found was that you can switch the memory size in your camera to hold more pictures, but then the quality of the pictures is compromised.
You will need a bigger memory card in most cases and then you can set the resolution higher to get better pictures. They say the higher resolution is for if you plan to really enlarge your pics, but my pics looked really pixel"y" or digital"ish" with the lower resolution.
Good luck!
Jenn