Old PACE TDS850 here, updated the other day. Since then I get regular momentary picture pixelisation with ascociated sound drop outs for about a second. Happens maybe 4 or 5 times and hour. If you wind back and rewatch the same bit though, it doesn't skip or drop out, or if you just watch with a few seconds of live pause on it doesn't do it either. Wierd. Sky know about this apparently.
Scrolling left and right on the EPG takes much longer to update the listing, I assume because it is constantly having to display the full program description in the top bar. Have had to slow down my scrolling behaviour to allow the channel listings to keep up.
A new box may speed up/solve these problems, however, don't want to change box until they sort out the DD 5.1 over HDMI issue with all current boxes. All in all a bit of a crap update for a Pace.