Engine: 4.8-litre petrol
Performance: 0-62 mph in 5.7 seconds, 21.9 mpg
Worth considering: Jaguar XK convertible, Maserati Spyder, Mercedes-Benz SL500
This week it's the turn once again of our north-eastern readers to deliver their verdict on one of our test cars.
Now, it is always with a glad heart that I head towards Newcastle. For one thing, it's a fine example of the sort of urban regeneration that has transformed our great northern cities over the past decade; in fact, the impressive Sage Building in Gateshead is probably my favourite spot for a post-test cup of tea.
But anyone who has a taste for pre-makeover Tyneside can still - just - see shipbuilding at Swan Hunter or step into the giant, 3D, real-time Viz cartoon that is Bigg Market on a Friday or Saturday evening. Marvellous place.
The appeal of any trip to Newcastle is further enhanced by the fact that it invariably involves a long trip up the A1.
The Great North Road is not universally loved but its varied stretches of motorway interspersed with narrower, less modern sections of carriageway, complete with crawling trucks, awkward junctions and big roundabouts provide the tester with plenty of opportunities to see what a car is really made of.
Few make such short work of the obstacle course of the A1 as the BMW 650i convertible. The recently introduced 4.8-litre V8 engine is a creamy delight, and works perfectly in tandem with the six-speed automatic gearbox.
For most UK journeys, I'd probably prefer this combination to the more powerful V10 engine and SMG gearbox fitted to the last big BMW we featured on The Verdict, the M5 (the "M" version of the 6-series is mechanically similar) - not because it is better but because it is nicer.
My few quibbles are mainly minor, or questions of personal preference. I spent ages looking for cup-holders but couldn't find any - and personally, I'd opt for the closed 6-series rather than the convertible.
That's not just because the fixed-roof version of any given car is usually stiffer, cheaper and lighter than its convertible counterpart - some buyers will happily trade those advantages for the pleasure of open-top motoring. Where the 6-series is concerned, there is an additional reason to opt for the closed model; the convertible sacrifices the elegant curved roofline of the coupé on which it is based for a roof-up profile that looks a lot more awkward and angular. The convertible does look pretty tasty when the roof is lowered, though.
And it's also worth noting that this car is a good bit cheaper than the obvious rivals that we've listed in our table. A BMW bargain - now there's a thought.
David Garner, 45, architect, Newcastle upon Tyne
USUAL CARS: AUDI TT 225 COUPE , MERCEDES-BENZ E300TD ESTATE
Compromise as ever. Is it a sports, business or family car? Either way, it's a phenomenal machine. I tried to look at it without thinking too much about its being a convertible. It is surprisingly noisy with the fabric hood up. The convertible is 210kg heavier than the coupé, that's like having three people in the car. I'm tall and there's no room behind the seats for everyday- or long-journey comfort. I fail to understand why wood is used on dashboards. The power and auto box is smooth and immense. Excellent ride. You have to concentrate on keeping within the speed limit. Very easy to drive. Still prefer the 911.
Iain Moore, 31, hospital doctor, Newcastle upon Tyne
USUAL CAR: AUDI A3
The BMW 650i is a shark-like behemoth, but graceful even at low speeds. It has all the internal luxury you would expect. I found the driving position especially comfortable - expect for the steering wheel being too low and the extremely annoying indicator switches. I didn't even go near the iDrive as it looked mind-boggling. The engine is powerful and quiet at speed, but noisy with the soft-top down. It looks well as a convertible, but decidedly less pretty with the hood up. I was surprised by the lack of space in the back seats - almost no need to include them. Also, the boot space is non-existent. This is a superb grand tourer, but not exactly a performance vehicle.
Mark Nichol, 26, student, Newcastle upon Tyne
USUAL CARS: RENAULT CLIO, PEUGEOT 307
The design is amazing, although it loses a lot of character as a convertible. It's one of the best resolved of the new BMW designs, managing to look coherent and a bit odd at the same time. The interior is impressive and the quality is exceptional, but I'm not convinced it's as special as it should be in a car this expensive. It's spacious and comfortable to drive, though, and the ride has a nice balance between sporty and cosseting. The highlight is the superb engine. It's very quick and smooth, propelling you effortlessly. It lacks the drama I expected of it, but I'm sure the M6 will provide that. It feels more like a powerful motorway cruiser than an out-and-out sports car.
If you would like to take part, e-mail email@example.com or write to: The Verdict, Features Department, Independent House, 191 Marsh Wall, London E14 9RS, giving your address, phone number and details of the car, if any, you drive. For most cars, participants must be over 26 and have a clean licence.