The 9100 FX Air would be (and is) my choice.
As someone who wears glasses the combination of a grinding/welding mask which also supplies fresh air is very handy.
The fx is a little more cumbersome than just the standard 9100, but the 3m adflo system is very good. Suppose it depends on its application as to what will be appropriate.
Check the price of spares before buying. Also look at how long spares will be available. I bought a airfed grinding mask off evilbay that you couldn't get spares for.
I have used the adflo/FX system at work and liked it. I own 3m Jupiter airfed system that were about £100 several years ago off evilbay.
Andrew