If you like the P22 then you might also like the Ruger SR22. Very similar in size and weight but with an aluminum slide instead of Walther's zinc alloy slide. I've handled a few Ruger's and they are better looking pistols, quality wise, and I've read they enjoy a better reputation. Price is similar.
I too, desiring a threaded barrel / receiver union, went with Volquartsen. I bought two and they are spectacular. The down side, unfortunately, is they leave little room for improvement which places a damper on the tinkerer in me. I did change the stocks to B&C Sportsman Challenge stocks which I pillar & glass bedded. I also added an adjustable harmonic stabilizer to the .17HM2 version, pictured below. The other, not pictured, is in .22lr.
Cool project. Two big foibles of the 10/22 are a clamped in barrel and a single (as in one) action screw. The heavier your barrel gets the more these lackings will rear their ugly heads. Early 10/22s had threaded barrel/reciever unions and are far better but nearly impossible to find. There are fixes. If you want a fat barrel go with a carbon fiber tension barrel. Looks good, accurate and reasonably light weight. There are many methods of adding a second action screw to the 10/22 and in my opinion one of the best improvements that can be made, especially if you install a heavy barrel. Good luck, we'll all want to see your progress so don't forget, a picture is worth a thousand words.
Welcome from Florida Steve. Always fascinated with the English and European shooters. I've noticed that our UK friends always appear to be shooting foreign rifles. Are there any sporting rifles still being manufactured in the UK?
Sounds like a fun day. I hang the pop cans from strings and bounce them around until they're shredded or I hit the sting. When I do hit the string I always say it was on purpose, damn, I'm good. ;D