I bought one of these years ago, gave it a couple of tries and gave up - sold it on Ebay.
Then last year I went to a retreat where a Fiskars rep was doing a make and take using them - I rolled my eyes and thought it would be a huge disaster... 100% wrong!
Once I was shown how to use this, I haven't stopped using it on nearly everything I do!
Just a matter of holding it right and you can't go wrong - there are so many templates available, but my favourite is the circle!
Give it a chance and if you have trouble, try and get someone to show you how - once you know, you'll wonder what you did without it!