611A had some different internals, thinner barrel and different sights than the 611.
The 611 is considered the gem among 22WMR semi-autos.
I have one that I grabbed off one of the forums years ago for $600 and it included a VX-III 3-10 scope. Excellent shooter and so much fun to plink with.
The money they command today is insane. They are amazingly simple and reliable though.
