I want to replace the router/modem Comcast with a high quality for streaming

@ghdprentice - Xfinity just left after helping integrate my new Arris SURFboard T25 DOCSIS 3.1 Cable Modem, which doubled my internet speed over what I was getting with the previous modem.  Speed Test showed well over 500 Mbps now, which is certainly all I need for my home usage and which was well worth the $112 cost.

@pindac 

When doing a major renovation a few years ago I put in flexible plastic conduit with pull strings inside to help future proof the installation.

@mitch2

Glad to hear it. See how long you have that speed.

Xfinity would not touch my Modem / Router.

Also check your billing for extra charges. They charged me $100 to put in their router and a couple mystery charges. No cost other than the monthly charge told to me by the technician.

I was to follow up on the Cable Type, Run Requirement, with a question about Containment. 

I witness miles of Data Cable being Installed it is usually laid in a dust controlled environment and is usually concealed under a Metal Clad Floor Tile with Screening Properties?

I was to inquire if a metal conduit would have any benefits for routing the Data Cable? 

If you have access to fiber optic or DSL you could make the switch and stick with the router the provider supplies. I have a secondary mesh network router system that piggybacks via ethernet cable from the main fiber optic router. The only thing on my mesh network is my hi-fi system. All other devices run off the main router.

No major issues but no noticeable improvements. I just have the hi-fi system on its own network separate from everyone's electronic devices.