I have a 20 hp Honda with a 48" deck. I'm debating between these 3 TracVacs. One is on a trailer pull behind, one is one casters attached to the frame, and the other is directly attached to the frame with no support underneath. Trac Vac says for my particular mower the one attached to the frame with no support underneath is recommended. It seems this could potentially lead to undesired "wheelies." The dealer is leaning towards the pull behind selling me on the fact I can take in around and collect leaves without having to use my mower to move it around. ANother dealer told me the caster one was too "top heavy." What does your experience tell me?