I have had good and bad experience with Jaime. I agree with the description of the Mercedes engine kit (at least he has one available where no one else does). Lots of missing parts, lots of work not expected with a kit etc.
On the other hand, Jaime stood by me when my 8 inch spinner let loose on my Albi and self destructed. Gave me a reduced rate and quick service on a replacement.

However, Ive had terrible experience with Larry Katona at PCK - even worse than AZM. I built the PCK DR1 and the kit is a ripoff. Made Larry recut many of the ribs as he can't read a blueprint correctly! Much of the material in the design was either not there, or not cut to shape as specified in Larry Weiss's plans. Had to supply and cut many of my own parts because of errors. Could have scratch built it easier. I would never recommend PCK, but I might try Jaime again for some of his accessory kits. So AZM is not the only one.......

Seems these forums are a good place to pick up on info about suppliers.