Guys
I would recommend not to use the 2.07
(I had to revert to 2.06)

issues with general internet speed when all settings left at default

Just a finding, don't know if I'm late or not...

There is basically 2 versions of 2.07 firmware
- FW2.07 (Global??)
- FW2.07TM (TM certified)

There's probably other variants depending on region, but I'm not 100% sure.
What I know is that both firmware above can be used without any problem. The global firmware also supports IPTV... I have used and tested.

However the TM firmware has issues with OpenDNS not registering the correct IP address, hence you might have problem accessing certain websites. Domain blocking sometimes an issue too.

Global firmware you can get from international/US D-Link.
But I got mine previously by updating within the router firmware update function (under MANAGEMENT tab).

The 2.07TM can get from D-Link MY/SG site.

The 2.07TM will have something like this displayed in the HOME tab

I don't have a clue what this is, probably someone else can explain.
My DiR-850L originally came with 2.06 which I think has TM firmware, since it was given for UniFi subscription anyway.
Then, I use the built-in firmware update, and the router downloaded 2.07 global. It was running fine, no issues.

Then I gatal tangan and downloaded 2.07TM from D-Link Malaysia site and manually flash it. It was okay for a few days until I found out that it doesn't work well with OpenDNS. Domain blocking still works, but in the same time, you cannot access websites marked 'illegal' by TM.

Then I tried reverting back to Global 2.07 by downloading the firmware from US site and manual flash. Somehow this time I couldn't even connect to the internet for some unknown reason. Your result may vary.

Now I downgraded to 2.06 Malaysia firmware, everything works just the way I like it.

So my recommendation is don't upgrade to 2.07TM unless you are only doing 'normal stuff'