At this point I can’t honestly answer this question because I have no experience with 1 Gbps Internet services. However, my area is soon getting AT&T Gigapower service, so I may soon have an opportunity to do some testing.
I would suggest reading reviews of people who have gigabit services and what routers are working well for them. When you get a chance to test out some routers, please let us know what works well for you.
Keep in mind that even though you might get 1 Gbps to your location, most hosts on the Internet aren’t going to be able to push 1 Gbps to you. So if you do some speed testing, you may only see a few hundred Mbps being shown, but realize that is a limitation of the speed testing tool, not necessarily your service. The same applies for downloading files. The server you are connecting to will probably not be able to send you files at 1 Gbps. So the next logical question would be why bother with 1 Gbps service at all? Well, even though you can’t get 1 Gbps from a single server, if you are downloading or streaming from multiple sources at the same time, all combined you might start to fill your 1 Gbps pipe. Since each service should have ample bandwidth in theory you should not see a slowdown from bandwidth competition. Now all that being said, you’d need to have very heavy usage to start to approach 1 Gbps at this point in time. But in the future, with things like 4K streaming, 1 Gbps might start to get crowded real quick.