I have the best luck with them! I also think they can be the most rewarding in some respects. Some Polyphagids can *tolerate* dryness, but I know of only one that seem to be Ok with it but still needs humidity (desert roach) and moisture at one location in the habitat. My best example: I bought some Polyphagus aegyptica from Orin a while back. They have grown like weeds into adults and begun to reproduce. I keep them slightly deeper substrate than what Orin mentioned, and the bottom half is always obviously withholding moisture but not wet or soggy...just to where is barely holds together when a ball it squeezed in your hand and then falls back apart. The top half get sprayed until its pretty damp, then I let it get dry, but not too long, and then spray again. They eat oak and walnut leaves, and almost NOTHING else. A dozen of them might eat a Cheerio or two every week/other week, or each take a bite out of a carrot bit, but seem to not eat most fruits and veggies (though they may take one tiny bite out of it). Some fish food had gone into the enclosure and dissapeared, but only very small amounts. Nymphs stay burrowed, deep, and adults live just under the surface leaves.
Contrary to this my Therea stay a little on the damp side, and so do Ergaula, though they have both gotten a little dry from time to time.
Graham, from what you have posted about your work schedule, frankly I think you would probably do very well with Polyphagids based on my personal experiences with them. I would also recommend you get them from Orin to try out, his are the prettiest if you are particular about your livestock, but that's my 2 cents....
