The tiptronic will likely annoy the hell out of you, seeing as you don't like autos much. Not driven a 5 series tiptronic (only a sequential), only a 3 series one. Didn't like it myself.
Be aware, they are fairly easy to clock, though that particular model doesn't wear as well as its predecessor.
It would be an idle car for someone who has has a stroke, as your left side will do nothing at all - no clutch, no indicators, no full beam needed, as you'll have your idiot lights (fog lights) on all the time, simple because you're a beemer driver (and hence, according to Mrs TheBoy, have a small knob

).
Not that you will use them, but the dealers around this way - without mentioning names, but the one at Oxford and teh one in MK - are woeful. If the car has been regularly serviced by them, you may be buying in to a whole world of trouble. I know its now pretty much fully depreciated, but without history, BMWs can be more difficult to sell on.
Check service item costs - it may be fully synth oil - and check that none of the std service items are too shocking. Check tyre prices as well - I remember my brother's 1998 540 wasn't too kind on tyres, though he didn't have it long enough to have to change them.
But if you like it, and its what you want, then do your homework, and if it all checks out, go for it. Obviously, I would have to ban you
