I have the 40's that just were upgraded from the 30 version recently and are Sandisk Ultra. The 80 and 60 version are Sandisk Extreme and cost quite a bit more,thanks
Its more about read/write speed than pic quality. The Ultra is class 10 and read/writes faster than the regular class 4 cards. Recording video, quick follow shots require class 10. To answer your question you probably wouldn't notice the difference