Never seen these before, so can't say if they would fit for sure or not. As long as the are PAR46 and are going into our PAR46, what sounds to be a decklight, they should fit diameter wise. The problem with some LEDs is depth of the lamp is much bigger than halogen lamps and that can cause issues with fit even if they are technically the same size lamp. My biggest concern would be how to wire the light up. We use screw terminal connections in our lights and that appears to have a wire coming out the back, so not sure how well that all would connect or how involved you would have to get to make it work.
Based on price this probably isn't option you are looking for but for anyone else we just released our CG decklights. They are decklight version of X-LED spotlights. They are currently available in spot or wide flood. Can be chrome or black and whole unit is more economical than the flood lamps we were using before, since we make the whole light in house including the LED lamp.
http://www.unityusa.com/CG-Series-6-Decklight-S14_p_2836.html
Unfortunately the lamps used on these are not compatible with the old AG model decklights or the BG model decklights as the led is built into the head of the light instead of being a lamp.