Hi Claus,
I have one of those IYE Tornado beams with traveller+car in storage. Might end up on an F16..
Cleats we have gone through quite a lot of. The full metal ones produced in the 70s and scrounged from the scrapheap are the best.
Misalignment breaks blocks. Roller bearings breaks if overloaded. I dont know how many spi halyard blocks we went through on the T..
So far Harken have been mentioned, and Ronstand. How about other brands?