Nelly has always been a bit of a dilettante, borrowing any given hip-hop trend and filtering it through his pop-hop lens, and Brass Knuckles takes this formula to its logical end, with the St. Louis MC pilfering the sound of each track's featured guest. On "La," he trades verses with Snoop and Nate Dogg over production that approximates late-'90s West Coast G-Funk, while "U Ain't Him" (ft. Rick Ross) and "Hold Up" (LL Cool J and T.I.) parodies the stringy swoon of d-boy anthems. Nothing's particularly objectionable, and nothing is memorable either. This feels like Nelly on cruise control.