Making the Choice
There are two approaches to buying a router: buying what you need and trying to future-proof your purchase. If you're in the latter camp, read 5 Tips For Buying A Future Proof Router. Trying to get ahead of wireless router makers at this point is a fool's errand because Wi-Fi technology is still moving too quickly.
Jumping on the latest and greatest router with the intention of gettting ahead of the game isn't a smart way to spend your money. You'll pay $300 or more and are unlikely to see significant benefit. In fact, you're more likely to buy an expensive headache with not fully-baked firmware that will require more care than you have time for.
Our recommendation is to head on over to the Router Ranker, set the class type for AC1900 and choose away. AC1900 is the sweet spot right now for AC routers, providing the best combination of price and performance.
If you want to save a little and not sacrifice a lot of performance, look at AC1750 class products. There are some good bargains to be had for around $100.
If you want to spend under $100, look at AC1200 class routers. They'll provide good performance, especially if you have a small space and older wireless devices.
What about classes above AC1900? Our recommendation right now is to avoid AC2350 and AC2400 class products. These are first-generation 4x4 "MU-MIMO ready" products that provide no real benefit over AC1900, yet cost significantly more. They'll soon be replaced by second generation 4x4 AC2600 routers that will supposedly ship with MU-MIMO enabled in mid-2015.
I haven't talked about MU-MIMO, but you can read more about it here. That article also describes the technology used in AC3200 class "tri-band" routers, which I would recommend more than AC2350 if you really want spend the big bucks.
AC3200 provides the most benefit for those with a lot of dual-band devices, whether N or AC class. You won't see increased range, but should hear fewer complaints about crappy web video streaming in multi-streamer households, due to the router's ability to spread 5 GHz clients between its two 5 GHz radios. But if you already have another router (or two) converted to an access point handling your wireless network load, you probably won't see much benefit from an AC3200 class router.
Finally, you can forget about those classes in Table 1 above AC2600 for now. They won't appear until mid-2015 at the earliest and more likely toward the end of the year. You can read more about them in our CES 2015 Wrapup for now and they'll be covered in more detail in the next edition of this article.
By the way, AC routers do a better job of handling mixed (N and AC) clients than N routers did with mixes of N and G devices. See How Well Do AC Routers Handle Mixed Networks? for more on this.
The main thrust of this article has been to point you to the right class of router. Once you determine that, there is still a world of choice out there.
In the end, the only real way to know how a wireless router will perform is to try it. The SNB Forums are full of people agonizing over choosing the best router and getting confused by all the conflicting reviews and advice. Sometimes they get their "perfect" router home and all is well. But other times, it becomes the router from hell that won't play nice at all in their specific environment. If that happens to you, just return the router and move on to your second choice.
The better way to go is determine the class of router you need, hit the Router Charts routing benchmarks to make sure it has enough wired routing throughput to handle your Internet connection speed. Then use the Router Ranker to quickly find the best performing products. If you want to drill down into feature details, use the Router Finder and if you need to wallow in the performance benchmark data, check the Router Charts.
Once you've made your choice, buy from a retailer with a liberal return policy. Amazon has one and you'll get all your money back (minus shipping) as long as you return the product in the same condition as you received it. Linksys' Home Store has 90 day (!) no-hassle returns for new and 30 days for refurbed products and they pay shipping. There are other options out there. Use them to make sure that you're getting something that works for you!
Good luck and happy hunting!