I got to say. I'm a bit confussed about what the Mason Variation really is. On some sites diagram A is given on other diagram B is found.After looking over a couple sources. I feel it's most likely Diagram B. Seems to be the Move that the chess player James Mason liked to play. wikilink
To be honest I really don't care which openning is the Mason. In due time i'll most likely study both. I do feel every chess player. Should have familiarity with at least one openning that donesn't stick the knights out first. You never know when it's lessons might come in handy. Let's take a quick look at one of Mason's games and see what lessons it offers.
inspired by that game i decided to try it out for myself agaist the computer. My results were positive.