There's actually two models of MSI 660 Ti PE, one at 941MHz core, the other better one that OCs higher and more consistently, at 1019MHz core. The higher OCed model has a higher binned chip. The 1019MHz version actually beats the ASUS 660 Ti TOP even with much lower clock settings, including when both are OCed to their max.
I wouldn't really advise 1440p with either of those cards unless you don't mind playing some games at 1080p (BF3 being one of them), which it does pretty well actually at .31mm pixel pitch.
The Catleaps (or Overlords) are good investments in case you end up with a more powerful GPU or SLI on down the road. Hell, I play at 1600x900 and less on my 32" TV all the time and it looks pretty good actually. It's all about balancing res, screen size and viewing distance appropriately.