That is a pretty old/slow performing modem/router. 

I’d upgrade to something with at least docsis 3.1 as comcast has been pushing to get people on docsis 3.1 for a while. Even lowering speedtiers to make people upgrade. 

I’m a fan of getting a modem separate from the router so you control the firmware on the router. Its a bit more of a buy in but if something ever goes wrong with one of them, you don’t have to replace a combo unit.

Or you can go with a combo unit. If you’re not wanting AX, the SBG8300 is a docsis 3.1 modem with an AC1900 integrated router. You can find them pretty reasonable on amazon for either new or renewed. 

for the same price as a new SBG8300,  you can get the G34 which has an integrated AX router. 

So basically, if you’re going new, go with the G34. If you go renewed, the SBG8300 will be cheaper. 

Thank you for the info. I will now start to investigate pricing.