I use sphagnum moss for my laying container and incubating medium and had great success with her laying and all of my eggs hatching last year.
I first tried vermiculite but my female was searching frantically for a more suitable laying spot, once I switched out the vermiculite and put in moss she instantly went in and started laying later that day.
I also found vermiculite terribly messy. And with hardwood floors when stuff gets in the cracks between boards, it's a bear to try and get back out. At least moss is large enough that it doesn't go too far.
I just found the moss a lot easier to work with as far as getting the correct moisture level. With the vermiculite it was either way too wet or way too dry, I never found that happy medium. With moss, I just let it soak in lukewarm water for 20 mins and then came back and wrung it out by hand, fluffed it up in the container and voila.
And to me, everytime I see eggs being incubated in vermiculite it just looks too confining for proper air exchange for the developing embryos. You've always got that one side that's exposed to the air and the shell possibly gets too tough for proper hatching. Plus it looks a bear to take eggs out and check on their development and candling, etc. With moss, I just lift up the 1 inch "pad" on top and do what I need to do.
I also cannot find vermiculite locally so ordering online is another whole issue. So for me, moss is so much better. Plus after the eggs hatch, I just throw the whole thing in the compost heap. =)