Jon's prices are already lower than anywhere else, that i am aware of. i have never heard of him using a coupon. if you want a bigger price break, buy knockoff otherwise $81.50 is a steal for those lights since most places are $89.99.
I'm not sure about a coupon code for lonestarpse, but he has some of the lowest prices advertised allowed by the manufacturer, especially on Ghosts and other smaller LED items. He has better pricing than what is advertised on bigger ticket (more expensive) items, but he can't post the low prices. Give him a call for the lowest pricing on those items, like certain light bars and packages.
As far as which ghosts to use, it will all depend on where you're mounting them. Go with what fits the best. They both perform the same.