Another data point: I recently had an automatic transmission software update performed on my 02 4.4 by an independant at a cost of $95. I found the shift points to be pretty much the same in both the regular auto and sport modes. The biggest difference I found was how much more smoothly and quickly going into a shift was both when upshifting and downshifting. Coming out of a shift acted about the same. The overall experience "feels" smoother and quicker...but admittedly it's a very subjective analysis.

Not sure I understand why a BMW tech would recommend NOT upgrading unless there was a specific problem. In my own humble opinion, these updates might actually prevent issues from evolving. Maybe just me, but I feel a lot more comfortable knowing I'm running the latest and greatest software when it comes to BMW vehicles. For full disclosure, I am also one who believes in transmission fluid changes vs lifetime (or 100K mile changes).