2007 Giants- #6 seed and had a 10-6 record and had to sneak into the playoffs
2008 Cardinals- #4 seed (lowest of the division winners), 9-7 in the weak NFC West. (and they were the SB losers)
2009 Saints- #1 seed and eventual SB champions. (We had the game in hand so I'll give us this one, but the fact is, we LOST)
2010 Packers- #6 seed and had a 10-6 record (see 2007 Giants) and had to beat the Bears who had already sewed up the #2 seed and had zero to play for.
2011 Giants- #4 seed (lowest of the division winners) had a 9-7 record and had a do or die game just to get in.
2012 Ravens- #4 seed, 12-4 record and we had to pull out an OT win. So this one I'll give you also.
What I'm trying to say is most of the SB winners that we have beat haven't exactly been the cream of the crop and most of them got in on the skin of their teeth and were middle to low seeds. Beat more #1 and #2 seeds and I'll lend more credence to this.