Haha, he's hooked
Great shots Mike.
Something I worked out the other day with Imagestaker and Registax. Registax won't give you a much brighter image, which is ok if your individual shots are relatively bright, but Imagestaker adds the brightness of each image as it stacks. Well that's how I think of it anyway. I had a couple of shots that were a bit dark and Registax didn't improve them much. But when I ran them through Imagestacker I was amazed at how much brighter the final image came out.
If you've only got three images and you'd like to brighten the final, try doing all your adjustments first on each image and then stack them. Yes it means doing three sets of processing but the final image might make it worth it.