Looks like the same kit and same price from H-D.
http://www.harley-davidson.com/gma/gma_product.jsp?PRODUCT%3C%3Eprd_id=845524448774075&FOLDER%3C%3Efolder_id=2534374302290631&ASSORTMENT%3C%3East_id=2534374302290631&bmUID=1283468582741&bmLocale=en_US
I ordered the one from custom dynamics. The difference (according to CD) is the HD one has 4 LED lights and the CD one has 40 LED lights. The CD one is supposedly brighter.
Looks like the Custom Dynamics version does have a lot more LED's, though I'd be happy with just a replacement 'smoked' lens cover. I've never had good luck with LED's; the brakelights on my Suburban and motorhome both have LED's and some have burned out and looks funky. 40 LED's would just increase my odds that my Ultra would end up looking funky too.
I received my lens from custom dynamics late yesterday evening and had just enough time to unpack it from the box. I noticed that the base is like plastic injected with chrome painting/plating on it. Since I haven't removed the stock lens yet I was wondering if the stock lens also has the same plastic injected/chrome base.