OK, not a problem. Had you, up front, indicated that your intended use was for grins only, I would have been less emphatic about the downside. We do serious training at our shop and have seen too many folks buy and intend to stake their life on a laser device when we know the "darkside", that it could get them (or someone else) killed. Fortunately, that problem solves itself when they try to use it on a "safe" qualification course and fail.
As I said, I have some and use one to tease the crap out of our cats
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While not inexpensive (about $300), the Glock GTL21 with a tactical light and laser unit is a great unit that slips easily on and off the pistol rail. The LaserLyte requires substitute parts for the recoil spring/guide and takedown lever. I'm not sure if any other "permanent" modes are required.
With there being some posts about XD's locking up from recoil guide/take down lever issues, it may not be in your best interest to use the LaserLyte. I carry my GTL21 in my pocket or on the rail on my mag carrier. I use the light more often than the laser (the functions are selectable, light only, laser only, both, or all off). There is also a ambi-toggle switch for momentary or constant on.
The main advantage of the LaserLyte, as far as I know, is that it is compatible with whatever holster you already have. When LaserGrip does come out with a unit for the XD, it, like the one for the Glock, adds bulk to the right side of the grip area and could affect being able to use some holsters. Also, being a lefty, it is righty oriented and definately doesn't work in lefty holsters.
Just my $.03 (inflation you know
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