Any question answered...

is there a difference?

Can't find a single nice looking retro fender in that topic.

Any tips on how to get a nice clean chain guard (pants protection only so only the front should do the trick).

They make fun of the name, yet calling it a mudguard is no less a joke; try using one going through real mud. I would suggest fender is better because it fends more than one thing off, whether it be water, a little bit of mud or the odd piece of shit.
Regardless, I'm still wrapping my head around white frame, green lugs and metal style wheels.