If I'm assuming we're talking about a standard XD, then I don't know that you'd get a whole lot. It's a little shorter, but the overall height is the same (comparing an XD Service Model in .40) so I guess it depends on how it's digging in.
The part that appeals to me is the 12 round capacity.
Maybe see if a buddy has one with a holster you could try? That's probably the only way you'll know, short of buying one, if it'll fit you or not..
A good choice, I think, if it fits you and your intended use. I owned an XD-40 Service for awhile but found that I preferred my P229s. The 229 in .40 (or .357Sig) is smooth. I found the XD-40 a bit snappier, although not a problem.
The XD line is great. I am looking for a good used XD-45 Tactical at the moment.
I own an Xd .40 service model, and love it. I have fired around 500-600 rounds through it. All types of target, and sd ammo with no issues. For winter carry I use an Uncle Mikes kydex holster. For summer I use a Desantis ISB, and it conceals very nicely. It's a very well balanced gun, and very accurate. I do not notice the snap, that some people say it has. I honestly see any cons to it.
I've carried one daily for the last 1.5 years. Sometimes it's a little uncomfortable in my serpa, but all in all I love it. It's also 12+1, not just 12, yes I'm a smartass.
As for cons, people say it has a squishy trigger. It's just not a gritty glock trigger. It has a long take up, then a clean 4-5 lb break. They break in nicely by 1000 rounds, and a little nicer by about 5k. As for 10k I'll let you know, but it just keeps getting smoother.
If you're ever in the hammond neighborhood, I could meet you at the range and let you blast a few.
Look at my name. It was my first, and is my 99% of the time main carry. I have to show my XD9SC some love sometimes.
Pros:
Accurate
100% reliable
Shoots great, good trigger
Grip angle is perfect
Fully supported chamber (doesn't ruin your brass like a .40 Glock)
Can use lead bullets (Glock can't/shoudn't)
Easy field strip
Cons:
Just a tad too big/heavy for appendix IWB, but I do it anyway.
I bought my XD40 SC in 2004 and have carried it ever since. I carry IWB in a desantis tuck this and don't even notice it except when it isn't there. It's comfortable to shoot. I don't know what "snappy" means.
I don't know how much ammo I've put through it. A few thousand rounds probably. Eats everything. 180gr FMJ, 155 JHP, 180gr cast lead (nasty dirty stuff), Ranger-T, Lawman, hydrashoks, whatever. No malfunctions of any sort.
I liked it so much I bought a used XD40 Service for $350 about a year and a half ago.
It's got about a thousand or so rounds through it, same variety as the other one.
They are both great guns.
If you're leaning towards an XD Service, it might be worth looking into the XDm. The XDm is just a bit longer than the service, with 4 more rounds. I carry one in a Crossbreed Super Tuck daily. I haven't shot a XD 40, only the 45 Tactical, so I can't give an accurate comparison. If you want to shoot my XDm40 let me know, I live in Huntington.