Is it smart to upgrade from Benz MC20?

As you probably know, Benz has an upgrade policy. I can trade in my MC20 for an ACE for $450 or get a Glider for $600. My MC20 sounds pretty good on my SOTA Sapphire w/FMT arm. Can anyone tell me if the ACE is worth the extra $450? Or is the Glider the better upgrade for another $150?
In the summer, when the audio business is slow, you should be able to find a new ACE for at least $450 with out a trade, as I did. I've never heard the Glider but I'm very happy with my ACE, which clearly out performed my Somiko Blue Point. I plan on upgrading to the H2 eventually.