Well, it is installed and running great. The Setup Wizard has always been easy on D-Link products.
When configuring all my devices to point to it, all showed Excellent strength except two on second floor which showed good.
I'm OK with that.
As for performance, I didn't do any baseline on the DIR-800 this replaces so have no way to compare, but performance is very good.
I don't think I missed anything when configuring it, but I have a few irritations:
1) Idle timeout is too short and I see no way to change that. That was on DIR-800 as well.
These units are for home use. Pretty sure if I walk away from my PC for an hour nobody is going to sneak in and access it.
ALL D-Link routers have a timeout function. I believe it used to be 3 minutes. Not sure if that changed. Anyways, this is something that can't be changed. Ya, would be nice to have a log out button. Most other router Mfrs offer this. 
2) When I go to edit a client, the Edit Rule popup won't let me change the name, it's grayed out.
Even the manual shows the name grayed out.
I have 5 that say ROKU. Would be nice to add room name to it.
I presume it should be editable. What browser are you using? Does IE11 or FF do same thing? 3) On the Home Page, it says I have two, and some times three extenders.
When I click on it, it displays the Extender and sometimes a PC, sometimes a ROKU, sometimes both.
The PC is hardwired to the Extender,
Sometimes thinks they are clients and sometimes Extenders.
That seems to me to be a bug in the S/W.
What do you see if ALL Rokus are turned OFF? Besure any ROKU wireless broadcast is disabled. They are known to have there own broadcast.4) Initially it found the names of my two Servers and Two PC's. Now the PC that is hardwired to the Extender shows as "unknown"
Be sure that each device has a host name entered in to them. Most PCs and devices you can edit the Host Name.5) Fairly often the S/W will put a red X on the connection between the Router and the Internet and a red box that says "Click to repair".
Sometimes it turns back green, sometimes it doesn't
Manual says clicking the "Click to repair" button will take you to the Setup Wizard. It does not do that, it puts you at the login screen. Once you log in connection is OK.
I'm 99% certain it is not losing connection as the DIR-800 did not do this and I have no problems when accessing the Internet.
What is the Mfr and model # of the ISP modem?
6) Sometimes Connected Clients count drops to 0 or 1. If you click on the Connected Clients, the previous # of clients are there.
Maybe an issue in FW. Seen this before on the 890L and 880L in older FW.Now none of these issues seem to affect operation of the device and are just frustrating, but this web interface has been around for quite a while and
one would think it should be stable, unless however I'm experiencing problems due to F/W being 1.00, or I missed something in the fine print.
Probably would have waited buying had I know F/W was 1.00.
Hopefully updated to the F/W are on the horizon.
App wish list:
Be able to see what network it connected a device too.
Your input and feedback is helpful to let D-Link know of issues at hand and to help improve the FW.