Anyone wanna play a fun game? Let's go over the last 5 years of playoff teams and divide up those teams that are there with traded for/free agent QB's and those that there with drafted QB's. 
Broncos, Giants*, Texans and the Saints are the only ones i can think of who traded for a qb and made it to the playoffs in the last 5 years...
*giants shouldn't count.
broncos and saints shouldn't either. honestly have no clue who the texans qb is. david carr? (joke)
went and actually looked.
Traded qb's and FA qb's to go to playoffs
Eli Manning (Giants 07)**
Matt Hasselbeck (Seahawks 07)*
Todd Collins (Redskins 07)
Jeff Garcia (Eagles 07)
Kerry Collins (Titans 08)
Chad Pennington (Dolphins 08)
Kurt Warner (Cards 08)
Jake Delhomme (Panthers 08) (5 interceptions in first round)
Carson Palmer (Bengals 09)
Michael Vick (Eagles 09)
Kurt Warner (Cards 09)*
Brett Farve (Vikings 09)*
Matt Hasselbeck (Seahawks 10)*
Matt Cassell (Chiefs 10)*
Michael Vick (Eagles 10)
Jay Cutler (Bears 10)*
Matt Schaub (Texans 11) (counted this even though T.J. Yates played in the playoffs)
Eli Manning (Giants 11)**
Matt Schaub (Texans 12)*
Peyton Manning (Broncos 12)
* Indicates 1 or more wins in the playoffs
** Indicates super bowl champs
as i said earlier, Eli doesn't really count. 20 out of 60 Teams that reached the playoffs got there with a traded for or acquired from free agency a QB. 9 of those teams actually won a game or more in the playoffs. and only 2 of those teams won the superbowl, which doesn't count because Eli held out.
think that is right. if someone can think of anyone i missed, please let me know.