I feel sorry repeating myself this in the 1 forum, but my opinion only: at the moment, bmw is basically giving away ($299 for 27 mon) its 3.
http://www.bmwusa.com/standard/conte...OKSngHyxYV6/Mo
1. you may or may not eventually be tired of the 1er for its styling, size, power, or whatever reason. same to any car. but due to the size, make this car very small room in U.S.
2. since you have a family with kid(s), a 4 seat generous sedan seems more suitable.
3. As mentioned, current lease promotion is really cheap, and you can switch to 2013/4 model of 2 series, or new F30 3 as you wish for the short leasing period.
4. No worry of the initial depreciation and any dents etc (headache if you buy it)
If i did not bought my car three months ago or i have a friend could let me test drive more and give me some better suggestions, i would definitely lease a 3 (it was 349 months ago).
Anyway, table with your family if you value my regrets above.
Yang