Modded raiders or fireballs?

Which is cooler?
Which (for some reason) is better performing?

Depends on if you have the bearings already or not.
If you already have the bearings save the cash and buy the fireballs, if you don’t buy the raiders since whey come with the bearing. That way all you need is the plastic spacers.

I’m going to do a gift trade with my friend on our birthdays, and I’m looking more towards the “coolness factor.”

A Raider is just a Fireball with a bearing and spacers instead of a transaxle. If it were up to me I’d pick the one with the brighter colors.

what are some of the brighter colors?

Well if your going coolness factory buy special edition ones. There are tons of alternative side caps for raiders and fireballs.