TX, sorry about the delay in answering your post,, having problems getting into the forums,,,
The Pro is an excellent weapon,and yes it can be easily changed from 357sig to 40s&w,uses the same magazines,, the weapon tends to feel a little blocky to me,and about in between the 220/226 and the 228/229 series. If you are going to order it from the factory have them do a trigger job, it helps.. the transition from DA to SA isn't hard just takes some shooting,,if its not what you want you can always get it in the DAO