I have had several wildcats in the past and currently own a couple, I do not see peoples fasination with them, other than being able to brag that they have something there buddy doesnt. Most of them offer no real usable advantage over the standard version compared to the trouble of fireforming brass. The 243 AI is better on paper but really offers no usable advantage over the 243. If you are looking for a little more velocity out of the 243, I would strongly recomend a 6mm Rem., it is a standard round that brass and factory loads are obtainable, also you dont have to order custom dies. Also if you ever go to get rid of a wildcat gun, you will find they have no re-sale unless you happen to find someone that is looking for that exact gun. You will take a beating on it.