I have the o-grill as well. I like the look of the Blackstone griddle but in a perfect world I could find a griddle that would fit onto the O-grill I have. So far, no luck.
2008 2500hd Silverado Duramax
2011 Northern Lite 8.5 lite
2006 Wildcat 27bhwb fifth wheel
2009 Lance 830 (sold)