Yes, these links are allowed
These are 8x media. Sorry but I'm not very expert in NEC burners. Do your nec is a 8x capable burner on dual layer media? If not, I suggest you to buy 2x DL media, because burning a 8x media @2x can give you bad results even with a high quality media.
Moreover, many users here in the forum burned the verbatim 2x DL media also @higher speeds with great results, so with the 2x media you do a safe buy.