dczifter probably wrong, sorry.
i have had the line -x on for about 4 years and i am completely happy. it was spendy right at $350. it has a lifetime warranty so i felt the up front cost was worth it. just a couple days ago i had two good sized guys in my boat and we went through a shallow riffle. we drug bottom, but slid through. a guy behind me tried the same thing and got hung up. the only draw back was i think it added maybe 10 to 20 lbs to my boat. hope this helps