I think though buying any new car is a lottery regardless of manufacture, Maniac I think you have really just been unlucky with your particular Zed, you have to remember were probably in a minority who voice any problems or even discuss our cars and that the majority of E89 owners are perfectly satisfied. My own experience regardless of make;
1) Brand new Suzuki Swift GTI, cracked cylinder head after 1 month, 5 weeks in the garage awaiting parts, seriously damaged door whilst being worked on.
2) Brand new Audi A3 1.6 Sport, required new driveshaft seals at 3 months old, numerous window rattles.
3) Brand new Audi A3 1.8T Sport, rattling gear selector ratio, took dealer a month to fix as couldn't diagnose problem, numerous window rattles.
4) Brand new VW Passat 2.0 Sport, footwell trim kept detaching after numerous attempts to fix.
5) Brand new MINI Cooper S, numerous dash rattles, gave up on that one, failed headlight relay which sent all electrics haywire.
6) Brand new Peugeot 207cc 120GT, patchy paintwork all over the roof, bonnet and boot and gearbox whine, car rejected and new one ordered.
7) Brand new Peugeot 207cc 150GT, roof rattle from the start, dealer was inept and diagnosing fault, thought it was fuel tank so replaced this, to do this they had to drop rear suspension to get the tank out and dropped the car off the ramp onto the rear discs, unbeknown bending the shocks. The car was very interesting to drive crabbing across the road. Got rid after 2 months.
8) Brand new Vauxhall Corsa VXR, wing mirror housings cracked by themselves, replaced under warranty, door pulls would come away from door panel. Erratic power delivery, rear end rattles, got rid after 12 months.
9) Brand new Suzuki Swift 1.5 GLX, grinding brakes, leaking windscreen, suspension clunk when reversing.
10) 2001 BMW Z3, bought in 2008, been perfect.
11) BMW 118d SE, 4 month old demo, failed DPF at 12 months old.
12) BMW 118d M Sport, 3 month old demo, kept 2 years, was perfect.
13) Brand new BMW E89, a few occasional water drips on passenger side, engine whine when cold (considered normal), no other problems.
Just my experience of new cars of which BMW appear to have been the best upto now. The clincher for me as in Maniacs case is finding a good dealer when problems arise which is one of the reasons I've gone back to BMW. Vauxhall and Peugeot dealers were simply inept and unprofessional regarding any warranty work.
Forgot to add
Brand new mark 3 Toyota MR2, engine failure at 200 miles which required engine rebuild, was put down to a faulty bearing, had to fight tooth and nail to reject the car
Most reliable and fault free car was a Mazda 323 bought new in 1985 and sold in 2005, just required a new battery
Tim.