I've used both and don't really find that much difference between them. The crummy little thermometer that comes with either one are junk, though, IMHO. Plan to replace it.
I do think the styro bators, in general, tend to drown the chicks. Its really our fault, because we follow the directions and are always pouring the water to them. Im a big advocate of 'dry hatching' and so moved away from the styros for that reason.
I also reckon they are too crowded and so I prefer something a little bigger. Bigger usually equals more stable, too.
But I started with them like so many others, and they do work - even if they can be a little fiddly. Given a choice, I'd take the Hova Bator, forced air model. They have a "better" feel to me.
And their newest, high dollar ones are said to have eliminated much of the fussiness of the earlier models. But I can't speak to that, as mine were sacrificed long ago to make bigger, better models.
If you plan to use them, I would recommend you first read about dry incubation here:
https://www.backyardchickens.com/LC-DryIncubation.html