CM1150V and Comcast - can't get gigabit speeds?

Yeah.... I tried to follow every message thread on here I could find about this CM1150V and speed issues.  And honestly, at least half of the threads did sound like people were having problems with other things like line errors due to poor signal levels on some channels.  That, plus how few people seem to even own this new modem or want to use it on a gigabit speed tier with Comcast, makes it difficult to figure out what's really going on.

But I waved the white flag for now.  I surrender.  This modem is getting returned this afternoon and I fought with Comcast for another 2 hours on the phone to get them to re-provision the XB6 router they provided me initially.  (After they got it working for data, it was a big struggle to get the voice provisioning department to do their side of it. Ugh....)   It would be really nice if they'd leave BOTH modem profiles in their system so I could switch back and forth between the two for easier troubleshooting, but they won't.

At this point, I'm just hoping a version of this XB6 winds up a product end users can purchase.