router admin panel taking too long to load and speed issues

So I upgraded to Ultimate recently and I'm not happy with the upgrade experience.  I have internet but running into following issues:

Issues: 

•  The admin panel for the router takes incredibly too long to load and sometimes doesn't load at all.
• I'm promised speeds of around 300 mbps but only receiving 100 mbps (via speedtest). 
• Trouble loading the activation page which lists a model # that is slightly different the the Panoramic modem that I have. 

I was on the phone with a rep last night for 1/2 hr and nothing was accomplished.  Maybe it takes time to reach the full promised speed.  And I'm thinking the admin issues are related to recent cox site outage.   I've even reset the router TWICE and the rep reset it.    

I never had problems with my Netgear's admin panel loading. 

On the positive side, the Modem was new and was packaged well.    I was told "plug and play".  Funny.  

,Ricky