I used Autoglym kit (about £20) which comes with cleaner and protector spray.
Now I only cleaned it once using the cleaner spray, and took ages to wash all the foam away (using hosepipe with spray gun). Used about 1/4 of the bottle i'd say.
Then I used the protector (which annoyingly used the whole bottle to spray the entire roof). The protectant works really well and rain beads off lovely now.
However i'm now left with a 3/4 full bottle of cleaner, but i'll have to buy another kit if I want to protect it again. And i'm not 100% happy with the cleanliness.
Now this was my first time cleaning a fabric roof as im a soft top virgin.
Next time I do it, I plan to do 2 or 3 clean cycles with the cleaner bottle (to get it looking cleaner and blacker) before I apply the bottle of protectant after. Think I was perhaps a little impatient last time and wanted to get it done so I could drive it as i'd only had the car a week or so.
Oh, and before I purchased the kit i did some reading up on here, and as Ben G says above, others also said the Tutle Wax Protectant was pretty poor and Autoglym was much better.
Hope this helps
Dan