well the JO pro is stiffer then the anthem and much narrower as well
if ur more into jumpin the JO are amazing
if u like the feel of a fatter ski and do more jibbs then jumps the anthem is very nice
as for length id say go 160-170 depending on if ur centre mounting, ur ability, and preferance
if ur a better stronger skiier and/or centre mounting look at the bigger side of the spectrum