FWIW, I had the 900 and just gave it up a week ago because the lag got to me. I'm not sure why remotes and calculators are so far behind.
Also, you can have the remotes switch between activities "seamlessly" as long as you program them with the TVs discrete on and off codes. So then when the next activity tries to turn the TV on, instead of it sending the power signal (then turning the TV off), it just sends another 'On' signal, leaving the TV in the on state. I'm currently looking at Xsight and URC. Still haven't settled though. URC seems nice, but the ergonomics are bugging me.
EDIT: What I meant by lag, was the screen, not the actual IR signal. I'm realizing now that's obviously not what you meant. Oops. Even with the RF to IR transition, there wasn't much noticable lag.