My first two years as a vegan I did not try any of the commercial vegan cheeses at all.  They just didn't appeal to me as I was not a big cheese or dairy fan.  I used nutritional yeast homemade "cheese" sauce varieties in my recipes, and made homemade cashew cheese using agar flakes, nutrional yeast, and cashews once. 

But one day I had a craving for grilled cheese sandwiches.  I did a little research and it seemed that Daiya is quite successful as far as melting goes, so I went out and bought some (the wedges).  OMG it was so good!  Very authentic, tastes much like real cheese from what I remember.  It melted very well and fulfilled my strange craving for grilled cheese.  The only issues are 1.  one package doesn't last long as it is kind of small and 2. it isn't that cheap and can be hard to find.  I bought it at a Whole Foods Coop.  None of the regular grocery stores where I shop carry it, but you can order it online through Vegan Essentials store.  At any rate that is the only one I have tried (the chedder flavor one), but I liked it very much.