How about
A ruger MKII
Very VERY accurate handgun. Great training gun and very reliable.
The SR22 has changeable grips too.Walther P22 has been my best .22 pistol by far. Changeable grips, trigger, total feel.... all good.
I agree with you that if the OP wants something to simulate his XD, then the Mark III is a bad choice.
However, I don't know how anyone can compare the SR22 fairly with a MarkIII? They are just so different.... One is a target pistol and the other a plinker/trainer.
I've shot both and I like both for different reasons. I think the SR22 is a good way to teach beginners about self defense and is probably a solid choice as an EDC for small women or those who have very weak hand strength. However, I think you will be hard pressed to see one outperform a MarkIII in the accuracy department.
You don't keep them in a safe when you're not home ?
(or you don't have a boat ??)
I am also looking. I have decided on the Walter P22 on the suggestion of a friend that is a firearms instructor/gun smith and my 10 yo daughter likes the feel of it.