I've used these multiple time and am still not convinced by them. At first the egg would appear ok on the top but when I flopped it onto the toast the bottom of the White was not cooked and simply ran all over the place - not keen on soggy toast. So, tried cooking for longer next time, still had a little white running over the toast and also hard lumps of white where it had over cooked. Still haven't found the right timing.
Also, be aware that if you add other ingredients you may find they release a lot of moisture that sits in and around the egg - and will end up on your toast.