There aren't many shut down defensive players in the league at any position with all the rule changes. But here are a few good defensive PGs that came to mind: Rondo, Duhon, Westbrook.
I couldnt really think of any lockdown guys. But who are the best? Some must be above average! Rondo is a consensus, Ive heard that Westbrook is good, even though Ive never really watched him. Then theres the big names, CP3, Deron Williams, Chauncey. Ive heard (only from Nets fans) that Harris is solid. Duhon has been mentioned and Hinrich. Is that really it?
Chauncy is probably the best right now. Good man defender, excellent communicator. CP3 is a gambler (AI style), not a good defender. Deron is a little too slow. Duhon is a little small, but solid. Rondo is a gambler and is a little small, average defender. Harris used to be excellent, but even he knows that his defense has slipped quite a lot - and I am a Nets fan.
I've always thought he was a very overrated defender. Hes not bad but his D has never impressed me that much and he largely earned that reputation when playing with Ben Wallace (in his prime), Rasheed Wallace, and Tayshaun Prince holding down the paint behind him. Rondo and Harris stick out. I used to think Harris was also very overrated but his defensive reputation has come down and hes rated about right these days. Hinrich is good. How about Keyon Dooling? Not a starter nor a pure 1 but a very good defender from what I've seen. Chalmers and Westbrook are some nice rookies with potential to be good defensive PGs but I haven't seen much of either one to judge myself.