I have been using Raggtopp on my Z4 and works great. It waterproofs the top and seems to keep dirt from staining it. The downside is it is $20 per can.
Has anybody tried using Scotchguard on their rag tops? I don't know why it wouldn't work just as well as Raggtopp.
We use the BMW kit. It's not cheap, but it lasts a long time and does a great job.
I've also found that RaggTopp lasts quite a while - at least 2~3 months, depending on the number of times the top is washed.
Tom
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.