The Patriots brought in a pair of safeties to work out for them Monday: Darren Sharper and Renaldo Hill. Sharper's 35 with health concerns. Although he's also a 5 time Pro-Bowler, who three times in his career hauled in 9 interceptions. He's a veteran free agent with 14 seasons under his belt and a Super Bowl ring on his finger.
Renaldo Hill doesn't bring the same pedigree. He's a veteran of 10 years, but he's been a bit of a journeyman, playing for Arizona, Oakland, Miami, and Denver. He's played in one career playoff game.
I'm not sold on Brandon Meriweather, and I don't think the Pats are either. He's got talent. But he wanders around too often. The Patriots' defense is based on all 11 guys doing their specific job. When that happens, the big plays (in theory) come. The Patriots don't like a guy going off on his own trying to force the big play to happen.
The Patriots' secondary also lacks experience. Chung looks sharp, but there isn't much leadership back there. Sharper, if healthy, can be effective in that role. Who knows how much he's be able to play, but at least with Sharper, you'd know what you'd get from him every down.