Complaint Review: Sure Financial Incorporated

I received a notice along with a check for $4850. The letter says I won a USA Mega Sweepstakes in the amount of $450,000. There is a $4100 processing fee which I am suppose to take out of the check I received. The letter says to call David Morgan @ 604 653-7044 before cashing the check, but no one ever answers the phone. The check looks real. When I put the Sure Financial (812 Main St  Los Angeles, Ca. 90014) name in the computer this rip off report came up. The letter is from Sure Financial and the check is from Oliver Sprinkler Co., Inc 501 Feheley Drive King of Prussia, PA 19406-2690. Is this a scam?