Why yes, I do. I have my car coated in Feynlab Ceramic (v1) and a layer of Ceramic Lite on top. The Ceramic Lite lasted about 18 months and lots of testing abuse, the Ceramic is still there, but I have put another Lite Ceramic on top now.
I also moonlight at a Detailer Shop where they are a Feynlab installer. As such, I`ve seen them all be installed and seen them all come back for repeat maintenance. The coatings aren`t quite the same as others (though I suspect that Gyeon Pure Evo now uses a similar blend) - nothing else is as forgiving in the application, at least up to the self healing products. You can apply them to the whole car, then come back around then wipe off easy, with no fear. Plus they offer the `candiest` look too I think, most like the old Zaino look. The self healing coatings are a lot harder to use, and I`ve never applied one of those, but I`ve seen them be applied and it`s much more difficult, though they also provide a levelling product to help. The performance from these is top notch.
Their supporting products mostly tend to be very good as well, though sometime the instructions aren`t great. The performance is usually excellent, usually geared for maximum - durability or cleaning or ease of use, which makes me think that their chemistry is well resolved. Feynlab`s support is also very good too.