I'm going with Die Happy. I've always loved their sound since the first listen and the vocals by Robyn Kyle are, I feel, one of the best. He had a good vocal range and excellent command of his voice; he put a lot of emotion into the songs. Wish they had more than two releases but the two they had were some of the best of that time! Who wouldn't love a band that printed a big smiley face as the label on their second CD, kinda like this
Daniel Amos has some good stuff but more in the alternative genre.
Daniel Band was more hard rock and I never really heard too much of their stuff.
The Big 'D' (Deliverance) would be a very close second! They had more of a heavy metal crunch to their style after they abandoned the thrash style of their first couple releases.
I definitely like Disciple and saw them once in Nashville, TN during GMA week a few years ago. Great lyrics too!
Dreamer had one release which was pretty good hard rock but not enough to garner the top vote.