I bought a 128i. It's great. Has everything I need except m-sport (just sport - m-sport wasn't an option up here in Canada).
However, every time I see a 135i, I wonder.
When I wonder, I run thru why I chose the 128i.
In the end, I come to the same conclusion - that I did the sensible thing.
But, I still can't help but wonder ....
Maybe I should've been less sensible.
0) I can afford both
1) In Canada, for the same options, the 135i is $7K more not incl taxes
2) I only plan to use it as a DD - no autox, tracking. So, I don't think I need the extra power
3) I've got two teenagers, 1 year and 2 years away from "daddy, can I borrow your car". I remember what I was like back then. I don't think they need to be driving a rocket.
4) Expectation that the total cost of ownership (e.g $insurance$, gas ...) will be more
5) Came off an 2001 Audi A4 2.0T. It only had 170hp. The 128i's got 35% more hp & the A4 was plenty fun. Did have that annoying turbo lag but, never any issues w/ the turbo (but, there were other problems
)
6) 0-60 is ~6sec. Back in the day, had a '84 225hp Mustang GT w/ 0-60 in 6.5sec. I thought that car was fast. Lost my license to too many speeding tickets - oops. Point is, this car is plenty fast. I wish it had more torque `cause you don't really feel how quick it is. The 130i engine would've been perfect!!!
7) Worried about the HPFP, injectors, carbon buildup ... issues I've read about. Personally, know of friends w/ 335i's that've had problems.
8) Plan to keep the car for a long time
Again, I decided to go for the 128i. I'm really starting to enjoy it now (after the break-in period & winter on snows) & the desire to get a 135i has dropped off significantly. In fact, I went and test drove a used '09 recently - I left thinking that I've got all the performance I need - just wish I had those m-aero bumpers. So, if you're like me, get the 128i w/ 6MT, m-sport, and spend/save the rest. We went on a cruise of the Caribbean instead.
Hope that helps.