Thanks for your comments chaps (and Helen
Yes, I seem to have dropped a little lucky with this car, it's not flawless, but at the price I paid (and it's age & mileage) I'd be foolish to expect anything else.
A few very minor paint chips which could easily be recified. Leather showing it's age but really isn't too bad (a client who supplies leather warranty/repair packs for sofas has got a packet of stuff for me that should help). The carbon trim on the door handles is pretty worn but really not worth £300ish to replace.
Had to put a new battery in a few weeks ago (replaced the original so just bad timing on my part), shoved some oil in the other day and the fuel filler cap broke yesterday which will be easy to replace once I find the part (will post a piccy up tomorrow as I'm struggling to find one - when you push the cap it flips out or push it again and it stays in - it's the clicker thing the cap leans against that's broke; if that makes sense).
I've even taken to turning the stereo off as I'm enjoying listening to the engine (must be missing my 350Z) and smoothness of the engine/chassis.
So, E46 330i or Z4M, no contest is it, the Z4M all day just think I'll have to be patient a little while longer.