I would have to say that at 460lbs, it is light duty at best. Weight is your friend when it comes to grading.
A "good" 6 foot box blade is going to weigh no less than 750 lbs. My Gannon 6" box weighs 1000lbs for a comparison.
Weight costs money, just don't go cheap and regret it later on.
Good luck with your search and decision.
