Who out there has a Bumbo?

The Bumbo is the much-loved babysitter, adored by my friend, Gwen, whose opinion I trust implictly. It is now widely considered THE must-have baby item. It was unknown to us prior to Kate, making it one of our baby items not previously tested on Will. We reluctantly admit that, at least for us, and at least for right now, the Bumbo is not a very popular item.
It’s best use (to date) has been as a photography tool. Kate definitely sits unsupported in it… for about 5 minutes. Then she begins to throw her arms back (see above) and can actually lift her little butt up from the chair. If it weren’t for the fact that her Michelan baby thighs get stuck in the leg holes, she would easy be able to catapult herself out of the Bumbo.
She also has a sideways manuver where she uses her arms to push out to one side — again, the thighs protect her from landing on her head (or in one of our plates, as we frequently seat her in the Bumbo as our dinner centerpiece.)
So we are left wondering… is Kate simply an errant Bumbo user? An unusually active infant? Is this something that she will outgrow? Inquiring Bumbo-owning parents want to know…