Rondo has played decent enough defense with Boston (yes they had other guys, but it was the team defense that made them. Saw them live in '08 when they won the chip when they came to sac, amazing team defense and made me want Thibs).
Marco played decent ball with the Spurs, and nobody plays if they can't play some defense under Pop.
Collison was an above-average defender with the hornets, clippers, and pacers, but hasn't ever been consistent enough on both ends to merit starting.
Overall the biggest defensive liabilities have proven otherwise on teams not named the Kings.