I am strongly considering a F3990 but would love to ask you some questions about your grass catcher. Is it a kubota model and how happy are you with its performance ? I currently have a Scag 61" deck 29 hp Kawasaki with a clam shell bagger and am continually fighting with it leaving a trail of grass between the 2nd and 3rd blade. Have had 2 separate dealers unsuccessfully diagnose what the problem is. I am mowing as slow as possible and having to make 3 or 4 passes to completely pick up the grass. I am ready to upgrade but my dealer can't find anyone in my area with a unit with a grass collection system to talk to and I don't want to be the guinea pig. Any input, advise, and or suggestions are welcome. Thanks Don