Who's everyone been playing against in their quest for 9-inning perfect games against the computer? I haven't begun attempting it yet, and I was curious who's the best to go after. Houston seems like the most logical opponent, since they have no power, but I could see Boston's lack of speed as helpful for avoiding infield singles, assuming you could avoid homers. New York is also offensively weak, although Strawberry could present a challenge.
If I were attempting this, I would certainly play against Houston. Not so much because of their lack of offense, but because I seem to always go into the late innings against them. I have the hardest time beating them by the mercy rule before the 7th inning. I think that they would be the "easiest" to have a 9 inning/no strikeout/perfect game against. I would also avoid California for the team that I'd play with, because they tend to make tons of errors for me.
In fact, I'd probably use SF or St. Louis vs. Houston. That's how I'd attack it.
For those of you who play ROMs, another good 1 player challenge is to try to beat the Cubs on Ultimate7's ROM without walking anybody--he made some serious alterations to the Cubs line up--giving ultimate power to 3 hitters, ultimate speed to 2 hitters, and an ultimate fastball to 1 starter.