I agree with your assessment of WS1 and WS2. WS1 in both barrels is not common and the fragile muzzles would not be my choice.
I've had a M21 26" 12 gauge with WS1 and WS2 chokes for many years and, fortunately, have not had an incident affecting the WS1 choke. I'll continue to be extra cautious to protect the muzzles.
My new to me M21 has 28" vent rib barrels which I much prefer to my 26" solid rib skeet gun. I've looked for years to get a 28" vent rib skeet gun; and it has 32" vent rib full and full barrels as well---lucky me. Such guns are not uncommon in the US but here in Canada they are really hard to find.
