Finally was able to find a griddle that was made just for my weber grill.  So far, it has been great.  The heat is the biggest problem that I have encountered so far.  You would never think that heat would be a problem, but with a griddle it has been.  Other than that, the only thing that is a negative is that there is no place to store it on a spirit II.  With the open bottom of that grill you are kinda limited. I have been waiting for the storage bag because that will give me more options on storage.  With that being said, it's a heat accessory.