They're similar in flex I'd say to the original Trouble Makers or more recent Dynastar Pro models.
181 is a great park ski length, but symmetrical skis ski extra short all mountain.  I agree that an extra long symmetrical ski would own, like a bit stiffer 188 Anthem for instance.
I told Jason Levinthal this on a chairlift at Squaw in January '06 when Line came around and did the grassroots shop demos.  He thought I was crazy cuz they had a lot of trouble selling 186 Pro models to anyone but sponsor worthy kids who weren't paying .
I told him there were 2 key differences, Flex and Symmetry.    The 86 waist Pollards from a few years back were burly in the 186 cuz they hadn't figured out how to mill the Maple thinner without skis breaking.
Now that K2 is making Lines with legit machines/tooling I'd be shocked if there wasn't a big Anthem in the near future.