If you get the Zenith, I don't believe the newer batches upconvert over component anymore. So if you planned on using the component outputs you need to make sure you get one w/ older firmware. (I forget when Zenith disabled that highly desirable feature - which they call a mistake. You can get that info on the AVS boards if you like. You may also be able to find info there on how to replace newer firmware with an earlier version.)
Also, if you have an extremely large screen you'll notice some cropping on the right side of the image, which can be bothersome if you have a projector with multiple sources. (If you adjust to compensate for the Zenith, your cable/satellite image may now be shifted too far to the right.)
Other than those two issues, PQ is outstanding.