I own this (birthday gift from the BF, last year).
First of all, I must say that I found a strong olfactory association smelling Numero Uno to two other scents: Colonia Assoluta by AdP and Mitsuoko by Guerlain.
Having said that, I have smelled all three side-by-side and Numero Uno brings some differences to the table: A more toned-down lemon top note. Pronounced moss notes (actually, Numero Uno is the 'mossiest' scent I own, and I own a few fougeres). Wonderful sillage and longevity, in just a few sprays (I have a feeling this bottle will last me for quite a long while). A very formal scent - I have trouble spraying Numero Uno on when it's shorts and t-shirts, I feel slightly underdressed. The bottle is extremely heavy thick cut glass, feels very substantial and kind of resembles a bottle of cognac or single malt scotch. A class act. Lovers of Colonia Assoluta, Rive Gauche Pour Homme or even...Tuscany by Aramis will like Numero Uno.