HI - I'm brand new to pistols and would like to get into competitive shooting with a .22. I've read reviews, held different guns, and shot a Mark III Standard. So, I've narrowed it down to the Mark III but I'm not sure which one I should get... Standard, Hunter, Target, or Competition. Then there is the 22/45 series which I'm not sure if I'm a fan. Right now, I'd like to shoot with open sights and maybe add a scope in the future so I'd like the longer barrel with keeping in mind the weight of the gun. Any suggestions would be greatly appreciated!