Welcome to the forum. The XD45 in the 5" model is a "Tactical Model" the 4" is the "Service Model" and they come in the full size frame or the compact frame. If the Compact frame feels like your pinky is looking for a place on the grip then you can buy a grip extension made by Pearce. I CC the XD 45 Compact 4" Service Model with the shorter magazine in a CrossBreed Supertuck Holster almost daily because sometimes I carry it in an Uncle Mike's IWB holster if I'm just running to the store. I have no problems with it and the CrossBreed is more comfortable than I even imagined it would be. The Compact Tactical model is an awesome pistol and I'm told that the extra inch can take some getting used to when sitting but in a holster with an adjustable cant that problem can be taken care of. Personaly i think you would be fine with the 4" model but if you want the 5" go for it either choice would be a fine one. I hope this info is helpful.- Johnny
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