My ds finds likes it and finds parts of it funny. He loves working independently and the instruction are clear and easy to follow. Now for me, he is writing without fussing, making progress and that works for me.
There will be negative experiences with any curriculum and many seem like the "In thing..." for a while and then another is all the rage. I like to get ideas, opinions and look at samples of any program. And imo, I've got two kids and what works wonderfully for one isn't a good fit for the other. I've come to believe that using what gets done and works in your house is the best curriculum.;)