CSS3 buttons or image buttons?

So I'm working on a mobile web app and I'm trying to decide which to use for button styles I have.

The buttons involve: - gradients - rounded corners - shadow

Here is a sample of both of them. http://jsfiddle.net/G26rr/embedded/result/

Mind letting me know how it looks on your mobile device?

Here is what I thought of so far for each.. CSS3 Buttons Pros - better load time on mobile users

Cons - the rounded corners appear jagged on Android

CSS/Image Buttons Pros - final product looks much nicer on my Android device

Cons - slower load times

Any input? What do you guys use on your projects?