Yup, most people get the C1.2 to ~ 1.5 or so on a 125 FSB. 1.6 @ 133 FSB is pretty rare. You have to use a board that allows 1/4 PCI @ < 133 FSB. The TUSL2 is a great board, but does not have this feature! The ABIT ST6 and Gigabyte GA6OXET are good bets for that setup.
C1.1 @ is a touchy one. It may make it to 133 FSB with plenty of Vcore. For some reason, the C1.0A and C1.1A have a harder time making it to 1.5 GHz than the C1.2. They need more Vcore to get to the same speed. For the C1.1A, I'd still get a board that allows 1/4 PCI @ any bus speed. Say you only make it to 130 FSB, 1.43 GHz. With a 1/3 PCI, you are @ 43.3 MHz....ouch. With a 1/4 PCI, 32.5 MHz....much better.
The C1.0A will surely make 133 FSB, 145 probably. A 1/4 PCI @ < 133 FSB is not a critical feature on one of these.