Ok so they emailed me back, not really with an answer, but they were very quick I suppose
"Dear Chris,
Thank you for your email. We appreciate your interest in our products
and the time you took to contact our Customer Service Department.
I am sorry, but the Optimus Prime Maquette is still in production and
the finalized product is not expected until the first quarter of 2011.
Once we have the finished item, we will know what the exact weight is of the piece.
If you send your question to our Production Team, using the Ask Sideshow link, they may be able to provide an estimated weight going by the prototype."
I submitted a question through the ask sideshow link 4 weeks ago though