Personally, I tend not to like most of the "1911" style .22s out there for the simple reason that pretty much all of them are made of zinc alloy. The Colt, which is made by Carl Walther, Germany and imported by Umarex is touted as having the frame made of zinc alloy, but the slide being of aluminum; I have seen tests on this gun that say otherwise, that the slide is also made of zinc alloy. The choices right now seem to be: GSG 1911 .22, SIG 1911 .22 (same gun as GSG but a little more refined), Chiappa 1911 .22, Colt/Walther/Umarex 1911 .22, and Browning 1911 .22 A1. All of these guns include some zinc alloy if not all zinc alloy, except the Browning. I opted to purchase the Browning. This little .22 is approximately 85% the size of a standard .45 caliber 1911. While smaller, it feels really nice in the hand and all the controls are EXACTLY the same and the gun breaks down EXACTLY the same as the full size 1911. Accuracy is pretty good too. Mine will group, depending on ammo, between 2"-4" at 15 yards and opens up considerably at 25 yards. Ten yard groups are in the 2" range. This is from a rested position. However, the Browning costs almost twice as much as the others with an MSRP of $599.00, although it can be purchased about $100.00 cheaper than that at some places. I traded in my Walther P22 on the Browning and am glad I did. It is by far the most fun .22 pistol I have ever owned. In over 800+ rounds of all types, and manufacturers, I have had 3 failures to feed; those I attribute to the ammo though. I believe it is the "1911" .22 pistol to own, if you can get past the size difference. I wouldn't have the slightest clue what the MK I would go for, but seeing how you can get them new for way under $400.00 I don't think $250-$275 would be out of line.