I just upgraded to 250 plan and I also purchased the same product now twice, both refurbished from Amazon. Both had a maximum speed of about 120 down and 12 up and spent a long time on phone with Netgear and comcast. Netgear tried everything that is in their script and told me that it takes 8 hours to get to full speed 12 hours later the same. I called back and they said to call Comcast and they couldn't help me. Comcast was very helpfull in my opinion and tried everything that they can think of. I am now sending back two to Amazon and ordered a new one, so I will see what happens. On another note, I was getting good speeds with their rented modem, so maybe they want to continue to rent to you for better profit.
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