I am 5-8 5-9 l weigh about 140 and I am thinking of getting the 150 or 153?
but I am not shore which would be better to get

Since u r looking at a freestyle / jib board, l assume u like to ride almost exclusively freestyle / park. Your weight is in the acceptable range for either size, so l would use a snowboard size calculator to get a rough idea of the right size:

http://frostyrider.com/tips/size-guide.htm

Beginner says 153 & intermediate says 155 for ur size, & since u might be growing or gaining a little weight this season l would say the 153 is perfect.

Good Luck

Well since your looking at a park only board l would go with a 150. It does not matter much that your growing unless next year you will be riding the same board. l am 125 lbs and 5 foot 5 and l ride a 148 in the park.

and l really dont think you are to big for a 150. Look at jp walker, hes probaly around 6 foot and atleast 150 lbs and hes riding 148.

you would be fine on the 150

l would skip the embarrassment and not buy an artifact. It is the worlds most overrated board.