None as of yet, it's been 6 or 7 weeks I think and I haven't had a chance to wash the van at all. This turns out to be quite good I think, it's rained a lot, and baked on, there's been the Saharan rain too, which has baked on now, and it's been hot as balls - so performance at shedding the dirt on the first wash will be an added dimension to the test (dirt rejection/ease of cleaning, rather than just water repellency). I'll be giving it the first wash this weekend for sure and I'm not really keen on seeing how it's progressing.
Cheers Steve, very much appreciated. I'm interested to see how these hold up! I reckon 4 months is probably the limit, given the prep I did (but I find it's not worth doing more and then only applying a sealant, if you're polishing you might as well go for a lightweight ceramic).