My MIL has an iPad and MUST have the stylus (old people apparently don't have the right skin to work them without.) She gets the one made specifically for the iPad, but I heard you can get good ones at the Walgreens counter as well.
I bought a stylus solely for the Draw Something game. I had to. I had so many games to keep up with and it made drawing easier on my iPhone.
Using your fingers for typing on an iPad would be more efficient than using a stylus but I think for general tappidy taps or games or whatever they're nice to use. Yes, you have to keep track of your pen but I've managed not to lose mine and I lose everything.
This one.
It's okay. I began to notice after much use you have to press a little harder and at the exact angle. I wish it had a pointy tip as well but it was only like $12 so you get what you pay for.