Shortboard confusion

Guys, just a quick question.
Have been riding a long board for three years, can go left and right and glide down the line no probs.
I am looking for a bit more adventure and thinking of coming down to a short board.
There is one for sale in my area, dimensions are 7'0" x 20 & 1/2" x 2 & 3/4". It's called a "big Boy".
Since I am 6'1", weighing 13/14 stone I am confused what I should go for.
I am also wondering is that above board a gun made for bigger waves.
All comments/opnions much appreciated.
Have been riding a long board for three years, can go left and right and glide down the line no probs.
I am looking for a bit more adventure and thinking of coming down to a short board.
There is one for sale in my area, dimensions are 7'0" x 20 & 1/2" x 2 & 3/4". It's called a "big Boy".
Since I am 6'1", weighing 13/14 stone I am confused what I should go for.
I am also wondering is that above board a gun made for bigger waves.
All comments/opnions much appreciated.