I've had a 'cord Vb, 'flex 3.5E, 3.5E2, and 2.8E. I much prefer the ergonomics of the 'flexes, but the taking lens on the 'cord was no slouch.

As for switching hands between focusing and winding - I don't find it cumbersome whatsoever. I actually prefer focusing with my left hand (I'm right-handed).