Can you switch out the bearings on a formula hub for something better?

I've read the bearings are "sealed" and that probably means they are similar to skateboard bearings and come off like a bearing would on a skateboard?

The reason I'm asking is I'm visiting relatives in the bearing business so they may have what i need if they are indeed replaceable~ And even then, what kind of differences am i going to be able to see with "better" bearings?

let me know what you guys think and if you have done it before~