Drafting QBs

Let's go backward through the past 10 Super Bowls to find starting Super Bowl QBs who were 1st round draft picks.

I'm going mostly off the top of my head here (the only guy I looked up was Chris Chandler), and I'm signifying the season, not the year.

2005: Ben Roethlisberger
2004: Donovan McNabb
2003:
2002:
2001:
2000: Trent Dilfer, Kerry Collins
1999: Steve McNair
1998: John Elway
1997: John Elway
1996: Drew Bledsoe

So, of the 20 opportunities to start a Super Bowl in the past 10 years, only 8 starters have been 1st round draft picks. In the last 5 years, only 2 of 10 Super Bowl starters were 1st round picks.

There are many ways to explain this, and I won't get into them now. But the question certainly presents itself: is it worth it to draft a QB in the first round?

Actually, another issue is also presented. In the past 10 seasons, how many of the Super Bowl starting QBs were drafted by the team they led to the Super Bowl?

2005: Ben Roethlisberger
2004: Donovan McNabb, Tom Brady
2003: Tom Brady
2002:
2001: Tom Brady
2000:
1999: Steve McNair
1998: John Elway
1997: John Elway
1996: Drew Bledsoe

Only 9 of the 20 Super Bowl starters were drafted by their Super Bowl team at all (and that includes only 6 different players).

Again, there are numerous ways to interpret this. But again, a question is presented: is it any better to draft a QB than to acquire a QB another way?

(update: just realized Elway wasn't drafted by the Broncos. However, since he was a rookie with the Broncos, it might be OK to count this with an asterisk)