I have one of those. It works pretty well. It's not so hard that most people will have trouble, but there are enough comments that it's too hard, that I have to assume it's a problem for people with little hand strength. It does not deal well with anything too large to fit into the bowl, like an orange. Tends to shoot juice out the sides.
This also works well, but you have to chase the seeds:
I reach for the olive wood juicer when I just need the juice of one lemon.