I used a hovabator last year and got 100% hatch rate. It wasn't like the one you posted. I have the cheap one that's on LLL reptiles. I didn't even have to use a thermostat (tho would recommend using one). The temps fluctuated a good bit, but nothing crazy. And when it got a little too hot, I would just open the top of the bator and let it go back down to the temp I had it setup. Only down side of this incubator is you can only fit at most 2 clutches. And NO you can not put the bp eggs like chicken eggs. You must set them up in a tub with vermiculite/perlite and do the water ratio. Or you can use hatch rite (ima be using hatch rite this year for my incubating). And if you expecting more than 2 clutches, I would recommend building or buying a bigger incubator.