OK I just got fiber installed today. As stated before, it's with centurylink. I decided to get 1gig service. I'm using the Archer C7 router directly with the ONT (ie, I'm not using centurylink's router).

I'm testing 750Mbps down. I'm testing 910Mbps up. I'm quite happy. According to https://arstechnica.com/civis/viewtopic.php?t=1312503 , this Archer C7 router is supposed to be the "value" option, providing very good speed for the price. I'd agree with that. I'm happy with the speed tests. However this is just the first day (just installed a few minutes ago), so keep that in mind. I'll try to remember to update here in a couple months with my longer-term review.

For anyone else with the C7, here are my settings (I'm not claiming that they are optimal... these are just the settings I'm currently using, which appear to work just fine):

For "Network -> WAN" settings:
WAN Connection Type: PPPoE/Russia PPPoE
<enter your own username and password for PPPoE>
..leave the rest of the settings on this page at the defaults...
(might want to "Save" first) but then click the "Advanced" button.
In the resulting page, called "PPPoE Advanced Settings",
put MTU Size (in bytes): 1492,
and click "Save"

For "Network -> IPTV" settings: (I'm not getting TV through centurylink, but still need to go to the "IPTV" tab anyway to enter the VLAN ID):
Mode: 802.1Q Tag VLAN
VLAN TAG for Internet Service: Enable
Internet VLAN ID: 201
Internet VLAN Pri: 1
LAN1 Mode: Internet - putting all ports to "internet" since I'm not getting phone nor TV through centurylink
LAN2 Mode: Internet
LAN3 Mode: Internet
LAN4 Mode: Internet
I did *not* check "Enable Multicast VLAN"

On "IPV6 Support -> IPV6 Setup" page:
WAN Connection Type: Tunnel 6to4
MTU Size (in bytes): 1492
Click "Save".


A few caveats: I called in to centurylink tech support twice to try to get the settings, but they were pretty clueless. They gave me a DSL setting (which doesn't apply since I'm on fiberoptic). I had to specifically ask for a VLAN ID and one of them gave me an ID that was *not* 201. They said it was 3158 which I believe is wrong simply because they didn't seem to know what they were talking about and I've heard 201 is the correct setting on a few different places on the interwebz. I haven't tried 3158 since 201 seems to work just fine.
Also note that I did set MTU to be 1492 in two different places... again I don't know if this is optimal, all I know is that it seems to be working fine, for now.
Also note that I am not really knowledgable about these settings or what they actually mean. I know enough to put them in, but that's about it. So please don't take these settings as authoritative.

Pink Jazz, thanks for the tips!