Is my 159cm snowboard too long for my shorter height and heavier weight?

I won a Sierra board a few months back and used a height/weight calculator to see what size board I should buy. It came up with the 159. I can’t find the original calculator but the one I just used ( http://frostyrider.com/tips/size-guide.htm ) says I should ride a 155-157. I’m about to buy binding and boots so I’m wondering if I should stick with this board.

My height is 5′ 2″ and weight is 240. I’ve snowboarded before, but I’ve always rented. I started off skiing and have skied 4 seasons and boarded 1 but haven’t done either in about four years.

The Product page for the Sierra board said the 159 is for “130-180 lbs.” but as I am shorter than the average person I decided to go with that one. I can’t find any stats for heavier riders around my height.
This is my board:

http://www.trusnow.com/Sierra-Reverse-Crew-Snowboards.asp

Sizing snowboards is mainly based on weight.
If anyone bases it on solely your height they are retarded.


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