from a while back indicated that Moe drove the ball 240 yards. These were in the time of persimmon drivers. If you look at some of the old Shell shows you will see that 240 is not so bad.
It would not suprise me for that 240 to go to 275 with newer technology. Moe had said in the interview I noted that he could get an extra 20-30 yards by turning more (and letting his hands go 'out of bounds' with a resulting lack of control).
Given this I'd not be suprised that Moe might hit the ball 290 with some swing changes but I've not seen any 'independent' confirmation that had the weight of those earlier reports.