And also do not replace one by the other.
Some people from the German 7-Forum and also now from the E34 Forum in German had contacted Pentosin. One got the reply by email, the other one talked with a head of a labority there.
To make the story short:
1. Where Pentosin CHF 7.1 is mentioned on the sticker of the reservoir, only refill CHF 7.1.
2. A mixing with other hydraulic oils could cause that additives could separat as a flocculent , which then could block valves etc. The instruction not to mix it is mentioned on the cans of the Pentosin 7.1
That is apparently also mentioned in a special internal BMW info for the repair shops.
3. CHF 7.1 contains special lubricants/additives, which are required by the older systems on E32 and E34
CHF 11S does not contain these additives in the required volume, it therefore cannot be used as alternative or replacement for 7.1 in case of topping up and/or replacement of Pentosin 7.1.
4 CHF 7.1 is green; CHF 11 is also green, but the colour is a slightly lighter green.