Why does this thread contain the word 'Fox' more than it contains '650i'
Anyway..
The 6 Series. A fantastic car - I love them. It's based on the E60 5 Series but is a better car in almost every way - though when new it had a price tag that was significantly more expensive than the eqiuvilent 5 Series. It shares components with the 5 mostly for technical and production reasons rather than because it's supposed to be a 5 Series Coupe - inside and out it is a more upmarket car. The interior is better built and uses more high quality materials, it's also far more asthetically pleasing than the E60.
If the 5 Series is a posh reps car then the 6 Series is most definately the MD's car.
Fabulous range of engines - from the reasonably frugal yet still powerful straight six 3 litre through to the potent V8's. The facelift in 2007 also brought with it the sole diesel model, the 635d, which makes a serious case for a great GT car because it also fixes one of the few flaws in the 6 Series - it's pittiful tank range.
It's a large waftable GT rather than a fun sports car.
I've looked into these a lot - I love how they look, I love the interiors, I think they are just really great cars and they fix most of the things I don't like about my preffered choice, the 3 Series. However it's not really on my shortlist, and the reason why will probably answer the second part of your post.
These cars are getting older now and accruing higher mileage. They are also very complex cars and virtually nothing that goes wrong is either quick, easy or inexpensive to fix. Additionally, quite a few of the more major components have to be specifically coded to the car. This makes a decent warranty a must unless you are so wealthy that you simply don't care about chucking 4 figures down the pan on a semi regular basis.
Once you hit about 70k miles or more the availability of a decent warranty begins to diminish. The BMW warranty becomes both useless and extortionately expensive - on this car it will cost in excess of £1000 a year and will also omit cover for various components and begin to class some repairs as 'wear and tear'. This leaves you at the mercy of the third party warranty companies who are very hit and miss - they try everything they can to wriggle out of a claim. Many, such as WD, also expect a contribution to parts costs which increases the further past 60k miles you go.
The 6 month warranty from the dealer will also not be worth the paper its written on - I know this from bitter experience with the E60 (Not going into this until its resolved). So whilst in theory yes you have rights with an independant trader its best assuming you don't, unless you want to have a massive fight in order to get those rights - it's amazing how quickly the trader turns cold when you pitch up 5 months later with a £2k bill.
So, that, for me, puts the 6 Series out of contention. They are simply too expensive to buy the sort of example where you can run it without worrying about bills - ie a low mileage example. If you wish to go for it you are a braver man than I, but I'll have a lot of respect for you as they are awesome cars. I've chickened out and am going for a 3 Series half the age with half the miles.
The 6 Series is a £60,000 GT car - it drives like one but it's also like one to run. The 650i is very thirsty as well, though at 6k a year you are probably not that bothered.
That said if you do go for it at that sort of mileage I expect nothing other than an immaculate car - they are well made and a decent BMW at high mileage can and should look as good as new. The reason for favouring low mileage on the newer cars is not because of their ability to handle high mileage, far from it, its because irritating failures happen at any mileage on these cars and warranty companies run away at higher mileage. So if you've got the spare capital to fix it yourself and you don't think you'll get bored, fast of fixing a BMW more than you really feel you ought to fix this sort of car, then that looks like a fabulous example.
At the end of the day, its a gamble. Up to you
