The HIDMatch lights I have on the 3 are my fogs (it came with factory HID headlights), and the color, intensity and throw match very well.
As for XenonExpert: The company is in Canada but ships out of Cali, and the owner's name is Olivier. He's a real stand-up guy, and ABSOLUTELY stands behind his stuff. I have had one bulb replaced under warranty and he was very quick to ship out the replacement. Mention to him that you heard about him on here or on the Mazda 3 Forum (mazda3forums.com) and he'll probably give you a discount. Another cool thing he does from time to time is run a bulb sale where he knocks the price down, and offers special pricing when you get more than one set (like if you were to get headlights and fogs at the same time).
He also has some killer HID replacement/upgrade kits. Check them out.