I've been reading posts about chain & sprocket modifications, but I am unsure of a few things:

1.) If i go to 43 tooth rear spocket and leave the front alone and want 520 chain will i have to change the front sprocket to accomodate the 520 chain? I ask because looking at spockets at indysuperbikes.com it specifies either a 520 sprocket or 530 sprocket, so i figure that's what size the chain needs to be. Is this correct?
2.) Besides size (i'm assuming it's size), what are going to be the differences between a 520 chain and a 530 chain.

Sorry if these seem like stupid questions, but i'm an FNG to the bike world. And to be honest, I'm not looking for a performance gain, it's more costmetic with the chain and sprocket. Just bought a MR hugger that doesn't have much of a chain guard, so the chain and sprocket will be more exposed and so the need for a purdier chain and sprocket. I guess i'm a pretty boy. At least i picked the right bike though, huh?