What do you want the most, zoom or pixels?
Basically the more pixels will only relly matter if you plan to print them out in a larger size, it will make very little difference on screen. Then again, how often will you use that extra zoom?
I had the C-700 and it produces good quality images, my acceptance rate on here shot up overnight from slide / film scanner processing. If you want to print them off at more than 7" x 5" you'll need a 3m pixel though.