As a firearms dealer I've handled many of both but have not fired either. The Ruger has the appearance of being better built by a considerable distance.
Welcome M1911. I've owned the Colt M4 OPS and liked it. I've shot the M&P 15-22 and liked it. But when I bought me CMMG Sierra .22lr dedicated upper I liked it so much more that I sold the Colt. CMMG also offers a complete .22lr AR rifle. There are other good examples out there but these are what I have experience with.
That bastard! How dare he. I've got a CZ 452 Varmint in .17HM2 with a threaded barrel. I added a Timney trigger, pillar and glass bedded it. Holy shit! It's like a laser. Some photos for lusting.
That sounds like a lot of fun. Along the same vein (reactive targets) I want to try one of these really badly. http://www.cheaperthandirt.com/product/TARGET-203
22 rimfire is notoriously filthy. Some brands are worse than others. The black sandy residue is most likely unburned powder granules. I've had some firearms fill up with this to the point of malfunction.