Has anyone ever used a Lex-aire RS pro hvlp gun? They make some interesting claims
about why their gun is superior to others.
They say the standard needle and air cap
will spray all materials. etc.etc.

http://www.lexaire.com

I've been away from the business for over a year. Can't say that I've heard of Lexaire guns.

I would be cautious of hype product claims. Most of them say their's is better than anyone else's.

The size of the cap is selected based on the material to be sprayed. A cap large enough for primers and clearcoats may not be suitable for colors coats and vice versa. Cap size is even more critical on hvlp guns.

I prefer to use a #10 conventional and a 1.7 hvlp cap, but I wouldn't recommend those unless you are relatively experienced. Caps that large for anything but primer-surfacer can make a big run in a flash if you're not careful.