G lenses with different versions?

[Monte920]

Today I had an opportunity to meet one of my friends who own a G1 + G45 lens. I was surprized to find that his G45 had different colors of coatings than mine. One had a serial number started with 7, the other started with 9. Please see the following pictures:

7:

9:

7:

9:

7:

9:

Putting together:

My questions are:
1. Are there two or more different versions of G45 lens?
2. Does the latter serial number mean that the lens was produced latter?
3. Which would you choose, if you were offered an chance to?

Thanks in advance for your answering!

 

[Cron]

interesting!
I have not known this until today, but I know there is also different coating by Leica lenses of one production series (eg Apo Macro 2,8/100).
Maybe modern coating used with same optical design will be better? I don't know.
I would choose the coating which my other G-lenses have.