Never heard that one -- they both had 8 X .303 cal. Brownings when originally designed until the Spit moved up to 2 X 20mm Hispano's and 4 X Brownings (20 mm more effective against Jerry bombers) ... you're only talking a few feet in the "spread" of the Brownings in Spitfire vs Hurricane -- sooooooooooooo ... if you are a good shot, you're a good shot.
Not sayin' it's not true -- just never heard that particular preference in the Brit fighters. Most first-person histories I've studied preferred the Spitfire for it's performance ... but there was the occasional die hard who liked the Hurricane. And the A-4 ....