I'm disappointed to hear about your Zebralight. I've been meaning to buy one for a long time.
I'll go into a bit more detail for you...
I actually bought all three models about 3 months ago. On my expense report, it was as a way to quickly test the efficacy of the CREE LEDs for use in a cell phone product I am working on. In real life, I wanted to see how they performed otherwise. I usually get to keep any samples for personal use.
The H30-Q5 has problems cycling through its 3 brightness phases correctly. Often it skips the brightest phase. It also comes on accidentally. That little rubber push switch is too sensitive.
The H50-Q5 works well, but twisting the cap to cycle the phases is not preferable to me (it leads to a lot of twisting!).
I think the switch is a better concept, but it needs some refinement before it works well.
And, whether they have a switch or a twist cap, it would be nice if there were a memory feature on it where if I was using it on "high" it would restart on "high" instead of going back to "low" every time.