Automatic Gearbox - Electrical faults. Spent much time locked in 3rd gear-get-you-home-mode.
Air Conditioning - Feeble & smelly.
Indicators - Failed at random. Traced it myself (See comment on dealers) to intermittent hazard warning light switch!
Horn - Failed.
Cruise control - Switched itself off at random with a loud click.
Glovebox - Poor fit, failed to open. Lock fell off. Had to take hinges off to get at documents inside. Internal release mechanism made from plastic(!), so it had fatiged, and finally broken.
Comfort - Quiet and comfortable, but the ride is not as smooth as the magazine reviews would lead you to believe.
Economy - Over 35 mpg on the motorway at a steady 70 mph (when the cruise control worked!). Excellent for a 3.0 V6 auto.
Audio - Speed sensitive volume control saves you from being deafened when you stop at the lights.
Electric rear sun-blind!
What's not so good?
Weight - A VERY heavy car, which only reluctantly goes round bends. Senator 24v much more fun, and quicker too.
Auto-dimming rear view mirror - No override switch.
V6 Ecotec - Not as smooth as the previous straight six in the Senator and Opel Monza.
Vauxhall Main Dealer Network - When presented with the problems, they were clueless. If you want an executive car, don't buy one from a mass-market manufacturer!
An electrical nightmare! Just an isolated example? I'm not so sure. It seems like Vauxhall build quality took a giant leap backwards with the introduction of the Omega. Sold at auction, after the auto-box started playing up again, only a few hundred miles after the last E.C.U change. I will never choose a Vauxhall again because I have no confidence in the dealers. Good riddance to bad rubbish!