I think it's a tough comparison to make, basically because we all know what the championship bench did for us during the season and playoffs, and on the other hand we still don't know what our current bench is going to give us. You can judge just by reading the players names on each bench, but you can also try to factor in their past and (speculated) future contributions.
It's pretty fair to say that Rasheed is the best player on both benches, but Posey was just huge for us all season long and boy was he huge for us during the playoffs with all those daggers and defense. PJ brown made the difference, and people will always remember that jump shot during game 7 against the lebrons (going 4 of 4 from the floor). Then you have Sam I am who also had his moments, during the Texas sweep and during the third game against Detroit where we got back HCA while Cassel had five points in 8 minutes after not playing in the first two games. On this debate people have not mentioned Powe, and that incredible game 2 of the finals he had. There you have 4 players we will not have back (except something works out with Powe later, which is a longshot). A 5th player is BBD, who we still don't know if he'll be back or not, but who did not contribute as much during the championship season compared to this last playoffs.
At present time, you enter Sheed, Daniels, and the rest are all questions marks, except for House who remains the same player really. Tony is a non factor and seems like he will be dealt on the Daniels deal. Pruitt remains a mistery, same as Giddens, both are not proven. Scal was not on the playoff roster, so he could contribute now, but he does not make game changing plays very often. Scot Pollard played a few games for us, and only during the season so he doesn't count either.
The key we all now, is if BBD is back with us and if Scal is kept, and if there's going to be a backup pg. If BBD comes back, our top 3 bench players this season of Sheed, BBD and Daniels, are arguably better contributors on paper than Posey, PJ and Sam or Posey, PJ and Powe (BBD really didn't do much difference his first season imo).
Playoffs rotations are short, so what matters the most are your main bench players, not the whole 5 bench players (pg, sg, sf, pf, c). In that case, I believe our bench right now is really up to the challenge against our championship bench to say the least. On the other hand, as a whole team, the big three will be two years older, but rondo and perk are a lot better and more experienced, specially rondo's improvement.
All in all, I believe that only by getting BBD back and keeping Scal our team has serious chances of winning it all again, no matter if we loose TA + Pruitt + Walker or Giddens, and get no backup PG.
Rondo House
Ray Daniels House
PP Daniels Scal
KG BBD Sheed Scal
Perk Sheed