Exactly what Carlo says...
Here in the UK, petrol is so prhobitively expensive that you have to be earning a large salary not to worry about only getting 20mpg (either that or you just don't care!) in something like a 540i... And the 525i isn't actually slow in real terms... Yes it doesn't give you a kick in the ass a 540i will, but it's actually still a quick car... 8 seconds to 60, about 140mph... And it'll return near as dammit 30mpg on a cruise (i'm getting about 30mpg or so from my 520i on average, and i've been told there's nothing in it from the 520 to the 525 cos of a slightly taller final drive in the 525)... I was always confused too at why they did the 530i V8... Approx 200kg heavier than the 525i, and only another 26bhp, with much worse economy!
It may be a low spec cloth interiored "stick shift" to you US boys, and yes the metric alloys are a nightmare (though he's just put new tyres on them, and i have a set of 16" 5 spokes with tyres i would put on anyway, off a 540i i might add), but that's not the point... It's a damn sight nicer than most other things on the road here, and it's individual... You don't find too many E34 enthusiasts left over here, so a lot of them don't get looked after, but at least the used prices tend to reflect that (ie. VERY low... Much lower than a similar age E36 3 series will be) and you get a lot of motor for your money...
Oh, and i've seen some leather interiors go cheap recently in good nick! Nice leather, my 16" 5 spokes, it'd look just like a 540i (at least until i cold afford some nice 17" Rondell's).
And besides, you speak to anyone this side of the pond (ie. anywhere in europe), and they'll tell you an M50 engined E34 5 series is probably the most reliable car you could buy... They don't tend to go wrong, and the engines when looked after will do inter stellar milages! Whilst returning acceptable fuel economy...
1995 E34 520i SE Touring, in Calypso Red, Manual Box.