How much storage do you need on your ipad

For what?

Depends on your use.

You need a little more storage than you use.

Have you ever had a device with too much storage?

Depends on the format/resolution...say from 1 to 3GB on average, with exceptions outside that range, of course. Use iTunes/iPad/Movies to check.

If you have full length movies in your iTunes library or any tv shows that you plan on transferring to your iPad, how much storage space does the video take up on your computer's hard drive?

If you plan on transferring music from your iTunes library, how much storage space does the music take up?

The same for photos on your computer that you would want available on your iPad.

The same for 3rd parry apps. Some apps take up very little storage space and some take more depending on the app's function. Some apps create and store data locally on the device.

In regards to storage capacity, it is better to have it available and not need it than to need it and not have it - especially with the iPad since whichever storage capacity you decide on can't be upgraded later.

I've got a 50 minute HD documentary which takes up 1.4 gig - the SD version of the same thing is 567 meg. But like roaminggnome says it's best to get a more storage than you think you need than to have too little - and once you've bought an iPad you can't increase its capacity. On the 16 gig version you have about 14 gig to play with due to the operating system and the built-in apps taking up some space.