Burnett's stats for his first three years actually compare very positively to the other three safeties'. He did not start as many games as Collins, but he has more interceptions, total turnover plays, and tackles. He started more games than Sharper, but the "old" 42 was a critical backup who played a lot on defense his rookie season. That said, Burnett has exceeded his totals in every category except touchdowns. Butler's turnover totals are close to Burnett's but Morgan is a more active tackler at this point in his career.
Obviously, comparing the career trajectories of these different players is no guarantee that Burnett will have a breakout season in 2013. However, the fact that he compares so positively over his first three years to these other All-Pro caliber safeties certainly is a positive sign for him and should give all Packers fans hope that he will indeed be set up for success this season.