What I see are a lot of Rugers, Buckmarks, and a number of S&W Victories, plus some higher end target pistols.
If it hadn't been cold and wet yesterday, I was going to shoot my Nelson/1911.
My Kadet Conversion is a good shooter, but you need either good trigger control or a better trigger.
Can't speak to other conversions.
I wouldn't expect much out of my Plastic M&P .22 Compact, even though it is my most reliable .22 auto.
Since Steel Challenge is under USPSA, there are a multitude of Divisions, anything you would take to USPSA or IDPA, plus the .22s.