I've put many many many many many many rounds through my XD and I've never had any kind of malfunction at all, ever! My sigma on the other hand though......not a lot of problems, and no jams. The slide just locks back prematurely sometimes.
Got the gun back today from S&W and headed strait for the range. Shot 150 rounds with no problems,for now im happy. He said the barrel was keeping the breach from closing all the way causing it to misfire. He replaced the barrel and that seemed to do the trick. Thank God I was sick of wasting gas and ammo on this thing.
I went to the range las weekend to shoot my Mosin Nagant. I decided to take my Sigma with me and fire it since its been getting neglected ever since I got my XD. I had my first misfire with it. 1500 rounds and thats the first real problem I've had with it.