Newbie: E39: Dinan worth it?

[rlw@xxxxxxxx (Bob Weissman)]

Hi, all, I'm a BMW newbie, having purchased my first bimmer, a 2000
528i with Steptronic. I'm still breaking it in (250 miles on it).

I'm writing to ask those of you who purchased Dinan upgrades whether you
found the purchase worth it. I'm considering starting with the two
software downloads. I guess I'm wondering, if these upgrades are so good
and easy, why didn't BMW make them the standard software? Does gas
mileage suffer mightily? Emissions increase?

Thanks,
- - Bob
  rlw@domain.elided

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