I love mine, but I use it for more than just IDPA. I don't really see much of an advantage of the 5.25 model over the standard XD9 if you can't take advantage of the increased magazine capacity. I like the sights a lot better on my 5.25, so that may be an advantage, but other than sights and mag capacity, there aren't many more advantages. Maybe the longer sight radius can be an advantage depending on how far the targets are.
Now, if you decide to move over to USPSA/IPSC or 3-gun, there will be a big advantage.
The holster that comes with the 5.25 is junk. It works, but is nothing like a nice holster that one would actually choose to use. I use the magazine holder provided though.