I was looking for a fun car with a convertible top and the 128 was just right. Luckily found a certified 2011 with only 14K miles and got the price break and power train warranty to 100K. A key factor was trunk space since I plan on using the car for trips in my retirement. It will hold a 25 inch roller bag flat and a 22 on its side, and even more in the back seat - great for such a small car I am an engineer and I am impressed with the build quality of this least expensive BMW.
My 2011 128i Convertible has 8,000 miles with nary a problem. Changed the run-flats to Contintental DWS regular tires the first week and it was like driving a completely different car--much better ride. Comfortable seats and just a blast to drive. In some ways better than the 3 series--top down at least you have some useable trunk space with the 128. Almost went for the 135, but I'm happy with the power of the 128--engine sometimes lugs a bit taking off, but slap the transmission over to sport mode and it compensates and puts you into the sweet spot of the torque curve and takes care of the issue. Nimble handling. One of the most fun cars I've ever had.
Took delivery in Munich. Spent a month driving around Germany, Austria, N. Italy and S. France. This car was made for this kind of driving; it couldn't have been more fun. If it were any bigger, I would have been even more terrified driving through Italy. The top is so easy to raise and lower we drove with it down every day we used the car. Even with the small engine, it didn't lack for pickup in the mountains. The 6 speed manual transmission was perfect. Seldom needed the brakes, except on the steepest downhills. Got admiring glances from most everyone. Now, if it is just half as good as the 1994 325 with 213,000 miles it replaced...
There is no other vehicle with this combination of fun and convenience. I previously had two Z4's and loved them but this car provides the fun with a back seat and room for two sets of golf clubs in the trunk with the top down. For the money there is no rival. A comparable Audi is $10,000 more and you still cannot get a 6 cylinder. One negative is the satellite radio. There is a software problem that causes problems with acquiring stations. Two years and still not fixed. Shame on you BMW.
I have been searching for a RWD convertible with a manual transmission for some time now and while test driving all the usual suspects in the same price range (new and used) my 128i was the obvious choice. I wouldn't mind a 135 for the significantly increased grunt, but there was no such car available- either new and too expensive or used and too old and out of warranty. Nevertheless the linearity of the naturally aspirated I-6 makes running up to the 7000rpm redline a pleasure, especially with the top down. While true value is debatable (I don't know if I could ever justify the full sticker price of a new one) the build quality, ergonomics and all around driving experience is worth it to me