Long story short, Spurs fans are over confident right now and have forgotten this team has not won a 2nd round game in a long, long time. People seem to have forgotten that this team is injury prone as well. Yes, the new guys look solid, but there is still ups and downs and not a lot of time to gel or practice.
Fact of the matter is that regardless of whether or not you like a match up or don't, that the gap between the top 5 teams is really nil. It will be about who's healthy and playing well. Match ups will be important, but from a talent and roster holes perspective most teams in the West are pretty even.
Teams with size are bad for the Spurs (Mavs/Lakers/MEM/OKC), Teams with below average talent are good for the Spurs (Hou, UTA, Den, Suns), but in either scenario there are virtually no series where the Spurs are heavily favored or dogs.
I rank the worst match ups as follows, but I say this with the caveat that the Spurs can beat all of these teams if healthy:
1)LA
2)OKC - DAL
3)MEM
The rest would be much more desirable. The absolute best case is the Spurs draw Houston/PHX/UTA/DEN in the first round while LA/DAL end up playing each other in the first as well. In that scenario, they can reach the WCF.