You likely want to know which Cable Modem you should buy for the fastest performance, lowest latency, and highest reliability. What does a network expert have to say?
But before we begin, here is the deal:
There is no "best" cable modem.
Any website that lists the "best" is full of garbage. Forget them. They are idiots try to sell you crap.
Modems should last for 5 to 10 years and almost never fail. They do not slow down with time. They do not wear out. Any quality issues are almost always an issue with the cabling in your home and/or from the street.
Modems do go obsolete. That is how they end up in the garbage heap.
With all that out of the way, here are my strict rules in terms of what to buy. There are NO exceptions to any of my rules.
Rule 1: Buy a Modem that is "approved" by YOUR cable company
Each Cable company has a list of "approved" modems that conforms to the standards. Definitely focus on the approved modem list, as the cable company has the unilateral power to cut off any modem it doesn't want to support.
Rule 2: Completely Ignore Marketing Speed Claims
All Cable modems can deliver very high speed data - much higher than what 99.5% of customers can use, and higher than what most home network equipment can deal with. Do not be fooled into buying the fastest multi-gigabit modem because it says "Fastest Multi-Gigabit Modem!!!". It's garbage. They're tricking you. Ignore them. While you're at it, ignore ALL the reviews. They're almost all shills or idiots.
Rule 3: Avoid Integrated WiFi Router/Modems
There are several reasons to avoid modems with integrated WiFi:
First, there is the obsolescence factor. Modems and WiFi are technologies that change at a different pace. Your Cable TV company will someday stop supporting your modem, and at that point you'll have to trash your WiFi router too? That makes no sense.
Second, the cable jack for your modem is likely in a lousy location for WiFi. You want to put your Cable Modem near the Cable TV jack, and you'll want to put your WiFi router in a nice central location appropriate for a broadcast radio transmitter.
Finally, Cable Modems are tightly controlled by your cable company. Cable companies have special access to your cable modem. The Cable company deploys all firmware updates and performs remote configuration on your device. I'm OK with that for the modem, but I'm not OK with the Cable company having the same powers over my in-home WiFi network. A combined device can give the Cable company power over your WiFi network. No.
Rule 4: Don't Buy What You Cannot Use
Don't spend extra to buy the mutli-gigabit modem unless you pay for multi-gigabit service and your home network is specifically engineered to deal with multi-gigabit speeds (the vast majority cannot). Typical home and business Ethernet networking is limited to 100 Megabit or 1 Gigabit.
Read the specs! I see on Amazon today that the most popular modem is a $150 1+ Gigabit modem with dual Ethernet connections. Then there is a very similar modem for $100 that says it "only" supports 800 mbit. Guess what? 99.9%+ of people will never be able to take advantage of the power of the CHEAPER modem. Why are people spending 50% more money for a modem they can never use? Answer in the comments.
How about a used or refurb modem?
Go for it. Make sure it conforms to the above rules, and like everything else in life, make sure that you can return it for its purchase price.
Just to be very clear here: I have *only* purchased refurb modems, and they have all been excellent.
How much should I spend?
I personally would never spend more than $50 on a modem, and I'd never recommend a more expensive modem to any of my customers. This may seem shocking, as all the top selling modems on Amazon are priced over $150. That reality shows how susceptible some people are to nonsense marketing claims.
The Cable Company Tech Said I Need A New Modem
Look, the Cable Company Tech would much rather have you try a different modem than to run new cables from the street to your house. Don't believe it at face value. If you buy a new modem because the tech said it'll fix your problems, be sure you can return that modem.
The Summary: What Does Lance J. Like?
My favorite is the ARRIS Surfboard SB6190. It is about $80 new, but refurbs can be found for under $40. The SB6190 has always flawlessly performed at the highest speeds for me. I'd love to know the reasons that people would buy anything else. There is no better modem to buy, although there are certainly more expensive modems out there.
I'd also consider models by Netgear or Motorola if the SB6190 were out-of-stock or something.