There's a lot of good info in this thread but here's my two cents. Last year I started about 40 cuttings using root riot. I used a standard nursery tray that had a clear plastic top with vents which gave around 10-12 inches of clearance. I misted the cubes nearly every day with a spray bottle and also misted the bottom of the tray a bit to keep the humidity up. I erred on the side of keeping them moist - very rarely did I let a cube even begin to dry out (as indicated by the color change). I had one or two cuttings that never rooted (probably because the cutting itself had issues) but I don't think I lost one to rot during the rooting phase. By the way, I used a light to moderate amount of rooting hormone. So from the point of view of simply rooting the cuttings in an efficient fashion they were great for me. Where things get tricky was potting up step. I had the best success putting them into peat pots which were then placed into 16 oz cups. I had somewhat less success with directly potting into 1 gallon. I did not use a humidity dome when I potted up. Most cuttings pushed out roots before leaves. Overall I was very happy with the outcome and would do it again if I had large numbers of cuttings to process. With just a few I use sphangum moss.