Gigablast not getting remotely close to speeds advertised

I wonder who at Cox thinks that Gigablast speeds are 140Mbps/35Mbps?  Because that's been the experience I've had over the past several months.  If I wanted the level of service I'm getting, I would have signed up for Verizon...Oops, I can't since Cox has agreements with the city preventing any competition. I've talked with support on the phone and via web chat.  The only thing they want to do is a reboot of the modem, and then claim that they don't see any issue.  Only when pressed on, do they mention having a technician come out to look at the issue, at $75 for them to come out.  

I thought it would be the panoramic gateway, but since I have voice service, I can't replace the gateway with my own equipment, not like Cox would allow that either. I have a brand new CM1200-100NAS that Cox has stated is supported, but every time I have attempted to activate the modem, I'm told that it's been registered to another account.  They can't explain how it's been registered as I purchased it at Best Buy, and have had to exchange it 3 different times because of the same "it's been registered to another account" issue.