You guys just aren't running those rascals fast enough. lol. Run'em wide open and it does a nicer job and doesn't load up with cuttings.
I have a SD60 and I don't see any problems with the mower design at all. I just run it like I stole it, blow it off, let it cool and the hit it with the garden hose, let it dry, then back it into the Garage Mahal.