.....within reason....
I had a decent drive yesterday, dropped Junior off with Grandparents, that, coupled with SWMBO nodding off on the way back, meant the MV6 got a boot down the a9 and through central Scotland for 100 or so miles. And boy did it get caned 
I am still amazed at how these things pull.
Specifically, crusing at 60-70-80mph steady, sports button on, engine note changed, and flooored. That acceleration from 70ish to err 80ish is really rapid..
I havent had a previous car that has accelerated in this range as the 3.0 does and ive had several hot hatches and a few BIG BMW`s. Chopped up and spat out an Impreza and a few big Volvos yesterday at this range...
I cant think of a car in sensible guiese / sensible price that can out run the Omegas Legs at this speed....
Anyone know of better?
They do go reasonably well once rolling, the big lardy ass isn't such an issue then

You do have to cane the tits off them though, I often find myself dropping to 3rd at 70MPH to get it going, barely any power at all in 5th at that speed. Not that I find that an issue as I enjoy driving my cars properly, but I think this engine is really crying out for a 6th gear to get the ratios a little closer making it easier to keep it on the boil.
My 840 will chew it up and spit it out at those speeds, due to an extra 100 BHP and better aerodynamics. Hardly a fair comparison though considering the price difference. Something like a Saab 9000 Aero with some mild tuning will easily accelerate quicker at higher speeds, and those can be bought for peanuts. Pretty reliable in pre-GM guise too I'm let to believe -- big let down is front wheel drive and general handling though, so the only thing it's really good at is straight line rolling start acceleration. Similar story with the T5.
I think the only real like for like competition is the E34 540i with 6-speed gearbox. Those are dropping towards £1500 now, have 286 BHP, great RWD handling especially in sport guise, and do pretty much everything the Omega does, just a little bit quicker. They're a lot older though, but come from an era when BMWs were built like brick outhouses, apparently much more reliable than the E39 if looked after. I'd probably jump at the chance if an immaculate one came up at decent money, but the pristine examples tend to hold their value a little better. Almost guaranteed to have less rust than an Omega, even with all those extra years of the paintwork taking a battering!
All-in though, I think the savage depreciation that the Omega suffers plays very much to its advantage when it comes to buying one 5+ years old. Not much comes close for the price. Reliability isn't great IMO (and the speed that they rust is a disgrace for a late 90s car costing nearly £30k new -- but then it's a Vauxhall, what do you expect) but they are reasonably cheap for parts, and just about DIY maintainable if you have arms like inspector gadget

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Oh and if you can find a dual-fuel one, the half price fuel bills make it even more of a bargain

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