I use suet baskets and they work pretty well for most eggs, but you have to be careful with really big eggs, sometimes they won't fit, or you can't close the lid completely. You can fit several in a Havobator with room to fill in additional eggs around them. But I'm going to give the bags a try, too.
John: I custom built a hatching tray with dividers, shaped to fit my Havobator, even used vinyl coated hardware clothe, was so proud of myself, couldn't wait to try it. The first time I used it I raised the lid and they instantly rolled out in all directions - looked like a swarm of ground bees, lol! Back to the drawing board!