I'm not really much of a press person - I have too short an attention span to use presses, as a general rule. I was intrigued by this one though - and thought I would give it a whirl.
I have to say - this is the most forgiving press-shape I have ever used. The real key to using the presses is the pre-press shape - and for this one - I went with what was essentially a mushroom shape. I was quite happy with the shape I got, and I found that having a little too much glass wasn't a big deal - the resulting ridge can melted in quite easily.
I also experimented with deeping the grooves with a small, sharp blade, and I like that effect too.
Overall - this is fairly satisfying press to use. Now, if I could only figure out what to do with scallop-shell beads!