The ROTA debate isn't really helping the OP is it?
Feel free to start another thread on it, and keep this one on topic.
All I would say on the metter is - Rota's are cheap, available quickly in the UK, look good, and have correct offsets for the Zed. Hence they are popular.
If WEDS or VOLKS cost the same as ROTA's, everyone would be buying those. It's not hard to work out.