You have a model 12 too! Now I'm getting envious!
It's one of my favorites to squirrel hunt with, being as it's light and holds several shells. And you can empty the darn thing in hurry, should the need arise. Possibly my favorite shotgun of all time. So much so, I'm looking for a 12 gauge sibling for it. Just can't justify paying the money that most of the collectors want for them right now.
My understanding is that squirrels aren't considered "game" animals in the UK like they are here. We hunt them for fun; as a matter of fact, my friends and I have dogs just for the purpose of treeing them. Most of us use 22 rifles as they tend to sit tight, but one of us always carries a shotgun for the runners. I either carry the Baikal sxs or the M12 pump when it's my turn. The pump holds 7 shots, and I only carry 7 or 8 more in my pocket. Weight is a big consideration when covering as much ground as we do. It's nothing to walk 4 or 5 miles on a morning or afternoon hunt; heck we've been known to stay out all day from daylight to dark. Best we ever done was 44 squirrels in one day. We stopped at noon and cooked 5 or 6 just to lighten the load!