I used thin wall tube and I wanted it stronger than floppy lawnmower frames. It's nice and rigid and should let the suspension do the suspensions job. My only worry with the thin wall tube is how it will hold up using plow or other implements on the 3 point hitch. Thick steel holds up better to impact even taking frame design into consideration and the weight helps the implements work. I wanted a light duty "all-purpose" type here, and hopefully it has enough power to utilize a snow/dirt plow, but not enough to destroy the frame when using it. LOL
