Remove and Insert Skateboard & Longboard Bearings

Not at all. Here's a video [VIDEO] on it (skip to 0:38). I'd recommend changing out the nuts, but I've had a Pennyboard that was perfectly fine with them rusted. I think as long as you can tighten/loosen, it won't be a problem. Here [LINK] are some replacements, and for new bearings people usually get Bones Reds. [LINK]

This [VIDEO] works every time for me, and you dont need any extra tools or a press!

I switched bearing fairly often because I was skating 2 different wheels with the same bearings and had trouble getting them in after a while because of dirt on the wheels. I personally wouldn't worry as long as you can put them all the way in. Just to be sure, you are using this technique, right?[VIDEO]

you can use your trucks to pop em off... actually, here is a youtube vid with more info than you'll ever need. [VIDEO] *you tube has no space

All you need is a wrench to fit the nut, remove the wheel from the axle, then remove the bearings from the wheel using this method [VIDEO].

this explains better [VIDEO]

Pry it off with the axle [VIDEO] Visual aid