I do like the guide rod laser best! Unfortunately, they don't have it available yet for the Px4 though.
Right now, I'm considering the laser to be a luxury item that I wouldn't buy myself. That's why I put it on my Amazon Christmas list along with a holster that holds rail accessoried Px4s and some spare batteries too.
I'm leaning toward the micro because it is the lightest and smallest. It also seemed to have the most positive reviews compared to the other fullsize lasermax. If they were the same price, I'd actually get the green laser, but I don't see why it should be double price. Just going by the reviews I've read so far, the micro beats the others.
I've also considered the light/laser combos. I've decided I'd rather have the flashlight seperate from the gun. One scenario is maybe I'd rather look like a guy walking around with a flashlight and not give it away that I'm armed.