What do you mean by more legit? Are you asking if one is a better quality memory module than another? If that's the case, the then the Crucial will probably be a bettery quality module than what you may receive from memorytogo.com. It's not uncommon for a price that low mean that you expecty to receive a generic memory module that problably doesn't go through the rigorous quality control of say a Crucial, Kensington, GEIL, etc.
Bear in mind the old adage. You get what you pay for.
Cheers,
Duke