This is a great question that I wish someone would chime in on.

It should be pointed out that we all know that the AmirII is an entirely different cymbal.

I have never read it explained why the differences in the font/size of the various Amir logos. I have read that Zildjian spent too much money on the Amir line, and thus they eventually discontinued it because the profit margin was too small.

but again - is there any difference in the different various sizes/fonts of "Amir"?

I have had/flipped a 20in Amir ride - but was not impressed by it (unlike Tim "Herb" Alexander who reportedly owned one as one of his favorite rides). I have never seen any Amir crashes in person. The HHs are very good - heavier/thinner sounding. I still have an Amir bottom - quite heavy......simply because it is a very good sounding heavy bottom.

I was working with Tim's drum tech a few years ago and I asked him about the cymbal that looked out of place with the rest of the gear. It was a 22 Amir. He told me it was the ONLY ride cymbal he ever uses.

I got the amir "by Zildjian" hats in and they look to be the same hammering pattern as the other 1st gen AMIR hi hats I have. So, I don't think they changed the quality/process until the small lowercase amir cymbals. I also noticed that the ones I just got and the all caps logo hats both have an AMIR stamp. The small lowercase cymbals just have the standard zildjian logo.