I think TCU is great, with Cinci close if not equal. Boise...good but not as close.
One way I like to think about this it to take other teams, and ask myself what they would do with TCU or Cinci's schedule. LSU, Ohio State, Oregon, Georgia Tech? They'd be undefeated I think, or at best a 1-loss team.
I also like to put those team's in an SEC schedule. I don't know that TCU, Cinci, or definitely Boise would be undefeated with Florida's schedule, much less Alabama, Ohio State, Notre Dame or LSU. I think they'd suffer 1-2 losses at least, and be beat up by the end of the year just like the rest of the BCS teams are. For the record, I think the same thing would happen in the PAC-10 or Big-12.
Given the current system, having TCU and Boise play each other is about as good as we can expect. It'll be a great game to watch, although it won't do much to help either team prove they can play with the bigger schools. If Cinci beats Georgia Tech, I don't think that will prove anything either, especially considering that Georgia Tech was beaten by a struggling Georgia team the week before they won the ACC Championship. Clemson got beaten by South Carolina the week before as well. I know those are rivalry games, but that's what big boy football is all about. More intense rivalries, more passion, more talent, more room for upsets and injuries. Even a playoff is a bit unfair I think because I believe teams like TCU, Cinci and Boise finish the season a lot fresher and healthier than Florida, Oregon, LSU, etc.