A lawsuit filed against Time Warner Cable is a reminder that buying a modem and router yourself is nearly always a better idea than renting the devices from your cable company.

New York attorney general Eric Schneiderman announced Wednesday that his office is suing Time Warner Cable, New York City’s biggest broadband provider, and its parent company over two issues. (The company was acquired by Charter Communications in 2016 and is officially known as Spectrum-Time Warner Cable.)

First, the suit alleges that Time Warner Cable and Charter failed to deliver the internet speeds consumers were promised—and that aspect of the suit has received the most attention.

Second, the Time Warner Cable is accused of wrongly assuring subscribers they could get those promised speeds via WiFi using the modem/routers provided by the company.

In response, the company said: "Charter made significant commitments to New York state as part of our merger with Time Warner Cable . . . We will continue to invest in our business and deliver the highest quality services to our customers while we defend against these allegations involving Time Warner Cable practices."

It's not only TWC customers who should look at alternatives to the hardware provided by their internet service.

One issue is simply cost. We've found that it generally sets you back $5 to $10 per month to lease a cable-company router, meaning you'll pay anywhere from $60 to $120 a year in rental fees. (Time Warner Cable subscribers, for example, paid $10 per month.)

If you look through our router ratings, you'll find recommended models that cost as little as $100. Simple math reveals that if you buy a router, it will quickly pay for itself, sometimes even within the first year of ownership.

Another reason is that a cable-company router may not be equipped with the latest technologies. In the Time Warner Cable case, for example, the attorney general alleges that the company supplied customers with outdated equipment, knowing that the routers couldn't provide the WiFi speeds it had advertised.

One final reason you may want to own a new router: We're currently in a golden age of router technologies and designs. Many of the newer models have sleek-looking designs you won't mind displaying in a living room and they can provide whole-home coverage, something you're not likely to get with cable-company routers.

While many of these new, high-tech models are expensive, they are capable of providing the higher levels of WiFi performance required in households—like mine, for instance—where multiple family members regularly stream movies, play games, or watch YouTube videos.

Whether you decide to get your own modem/router or stick with the one you rent, you'll want to get the best performance possible. Check out these simple tips for coaxing the strongest WiFi you can from the equipment you have.