I just bought a 3pt backhoe and here's what the dealer I bought it from said; He would not put a 3pt backhoe on a B series. (He sold both 3pt and subframe hoes, btw.) He said he never heard of a problem with one on an L series (mine) and that was what he was currently using on his tractor. Nevermind the warranty because my tractor was out of warranty anyway. Easy on/off and no subframe to decrease ground clearance. The "few hundred dollars" difference was $7,900 compared to $8,700 for a Woods compared to a Kubota BH.
On a personal note; I have no idea how this thing could fold up on me like mentioned above... I would like to hear more on that.
It's not loose or jerky if your actions are smooth, but I can see where a subframe unit would have an advantage here.
And I love this thing. I should have boughten one years ago. I trenched about 200' yesterday for some drain lines, moving huge chunks of concrete out of my way with ease. It took me four hours in a couple sittings, which I thought was pretty good considering I just got it. Nice smooth trench, but the ground had a natural fall to it.