These cars are and absolute pleasure to drive, magnificent but don't purchase one, they are a nightmare mechanically. Just ask any mechanic: water pump, radiator, cat converter, sensors, the list goes on...
Their appearance is second to none but beauty with these machines is only skin deep: I loved looking at my BMW but I was afraid to drive it anywhere.

I bought my wife a brand new 3 series Executive, paid $65k in 2005, within 10 months the auto blew up, great under warranty, what a Nightmare of a car. Every time we took this car to BMW the minimum cost was $1000. We still have the car, the engine light comes on often, we have replaced that many Valvetronic motors, we continue to get different lights all the time. 2 weeks ago I was offered $4000 as a trade in on a Merc, the dealer apologised to me for the insult, but as he said, the 3 series was the worst car BMW have ever sold. I would agree with him 100%.
NEVER buy a BMW, this piece of ......... cost us a fortune! Not Happy :(

Just picked up a 2013 316i very nice ex demo, I had a 320i which was traded in. The new car is a step up from my old car. Very good ride: comfort, good steering, very supportive seats, a well laid out dash and easy to read. Plenty of bells and whistles make this a good buy. Having looked at the competition I must admit I do like BMW.
Solid car great to drive
nothing yet

My mother bought this car brand new, a 1993 model, I purchased it from her when I turned 18 and it proved completely reliable for 21 years. All parts and repairs are completely affordable and realistic if you can do things yourself, but we never had a single problem at 320,000 ks, no engine issues, no transmission issues.
With cars like this, they must be maintained well, an oil change is the most important thing you can do for a car, and if you buy second hand, try buying from a reputable owner. These cars were designed great, care for it and it will care for you.

A little underpowered

I purchased a 2006 320i with 100,000km and full service history. In 14 months ownership I had multiple problems and estimate I would have spent $8,000 on services and maintenance issues including multiple oil leaks. I understand and accept that a second hand car will have faults but I have driven cars with over twice that mileage before that were a lot more reliable - I think it says a lot about BMWs build quality - the BMW specialist mechanics I took it to said this model was notorious for oil leaks. The driving experience was nothing special either. Much happier now I have got rid of it and purchased a Lexus.

Unreliable

I've had a 320i Executive sedan with innovations pack since new and have had nothing but trouble. Had to replace the thermo fan at 26,000km's and now the auto transmission has failed at 57,000km's and $10k to replace! BMW Australia want nothing to do with it - clearly a known fault with the car. A luxury sedan having this many major failures = no more BMW's for me!

Too many faults and expenses just out of warranty

I don't about you but when I buy a new car, I want it to work in every way but also to have style and to make me feel good and everyone I get in it, and the 320d does that for me. Plenty of power with frugality thrown in, size is ideal for 2-4 people and the fact that nothing goes wrong is a real bonus for me.
Not hassles, frugal on fuel, stylish.
Initial costs maybe?

I bought the 320i executive new in 2008. It's just gone 4 years old and 70K and has not missed a beat, everything works as intended and still on the original battery. Great handling and nice and easy to maneuver and park around town and holds the road beautifully at high speed.

The only downside is there is no wheel well in the boot should (and I would!) you wish to change from runflat tyres to standard type tyres. The runflats are a piece of mind safety feature but wear out way to quickly (on my third set). I've had a few nice cars including Mercs, VW, BMW's, Audi but my next purchase will be another Beamer.
Equipment level, build quality, handling, fuel consumption.
I would prefer not to have runflat tyres.

Bought a 1993 model 318i BMW earlier this year (2010). It seemed ok when I test-drove it. But I regret buying it after having to fix a few parts on in (from normal wear and tear). Parts cost 4 or 5 times (or more) than other cars types. All the electric gadgets are starting to fail and the airconditioner doesn't work any more. In its hey-day it would have been a nice car to drive for sure. But I think these are a bit too old now. Also if you're after fuel economy and a car that's economical to run in general... avoid buying this car.
Sturdy car. Handles well on turns/unsteady conditions. Electric options. Sunroof.
Parts are way too expensive. More likely to have maintenance problems with these older models. Too sluggish. Bad fuel economy.

I've owned a Mazda, four Audis and an HSV, and this 3 series is my favorite car of all. I was lucky enough to get a German-built version when the 2009 model first came out. No problems at all with build quality, not a single thing has gone wrong in 2 years.

I don't find the run flats to be too hard, but I came from an HSV with 19" rims, so anything was going to be softer.

320d engine has ample power and great delivery. Economy isn't flash - around town 7.5l/100km and low 6s on freeway trips, versus official combined figure of 5.4L. That's the only downside (other than purchase cost, of course).
Reliable, smooth, great build quality, good styling (with sport pack)
18" rims make for expensive tyres

My boyfriend bought this car when it has done 60,000 kilometers. It was a 4 door 1998 sedan. We really loved the car and wouldn't want to sell it if it wasn't too expensive to maintain. It was a wonderful car to drive around. However, when we had to fix anything it was so dear so we went back to purchase a Toyota.
Great German luxury. Great to drive. Excellent handling. Very easy and fun to drive.
Expensive to maintain which was the main reason we sold the car. The parts are very dear. Not very good value for money.

My 323i M Sport is now 18 months old. Had minimal issues with it, all fixed at BMW Melbourne with no fuss at all. Have just replaced tyres with non run flats, and it makes a world of difference to noise, ride and handling. Just needed to buy the "Mobility" pump/puncture repair kit from dealer.
Great car, a pleasure to drive.
Run flat tyres, limited rear legroom