I have read the same comments on my E39. I purchased the kit and sat on it somewhat fearful that if it is working, why mess it up.
Last year, I drained and filled the fluid. Last week I dropped the pan and finished the job. So far all is well. My 530i has 130,000 miles on a steptronic tranny.
I am original owner.

__________________
94 530i sold (That was difficult for me)
01 530i >144,500+ miles SOLD
06 330XI winter's especially fun drive (SOLD)
10 M3 Sedan (sweet)
13 Nissan GT-R Black Edition
13 Porsche Cayenne Diesel

BMWCCA 4215