Just a review of my experience.
The convertible I just bought for the wife as her daily driver is the first convertible I've ever had to care for. So, we have a local Shinerz Showcare
and I went to them for advice on the care of the soft-top. Turns out, owner is a convertible Mustang owner. If you didn't know (and I didn't) your top is made from sail cloth. Yes, marine sail cloth used for sails. I was happy with the results of this product. His recommendation was this:
I used it this past weekend and was impressed with the results. I have some advice from my experience though.
1. Pick a calm day. The protectant is an aresol can and will drift in the breeze.
2. Per point #1, cover your car to the point that only the top is visible. Save yourself from having to clean off the over-spray.
3. For the 1st application, use the entire protectant spray and apply in coats. Depending on whether your car is garage kept or not and your weather conditions, you should only have to apply again 1 or twice a year.
4. Keep the cleaner handy for removal of tough blemishes...I.E bird turds.