Michell Orbe platter upgrade:any comments?

The music will have a greater sense of ease. The sound will be more musical and enveloping. The background will be a little blacker as well. I definitely recommend this upgrade.

There was a recent thread at Audioasylum in the vinyl asylum about this, so you might want to search there. As I recall, about 75-80% of those who responded to the thread who had upgraded preferred the Orbe platter, but there were those who did not as well.

Not to complicate matters for you but I assume you are also aware of the Pedersen Gyro upgrade (http://home20.inet.tele.dk/pedersensgyro/)
I myself have the Gyro Mk II with the DC power supply. I think the Gyro does a lot of things well and looks really cool but its weakness is the suspended design which causes it to lack the real attack on notes and PRaT (Pace rhythm and timing) that mass loaded designs are capable of (think Teres, Galibier, Redpoint, Acoustic Signature/Solid, Platine Verdier etc.). It is such a "bouncy" suspension, any variations in stylus drag or motor speed are instantly translate to pitch variations by torquing the platter. I think this is the issue that Pedersen's Gyro mod addrresses. My guess is, the more massive platter of the Orbe may help this issue as well.
I also have an Acoustic Solid (actually my son's TT). This is a heavy acrylic over aluminium platter design which actually performs much better than the Gyro in the PRaT department although the AC motor and PSU are not up to the quality of the Gyro.
Let us know what you think of the Orbe upgrade compared to other TT's if you do it.