Asus RT-AC5300 need help with PS4 setup

[Fanee]

Dear All Gurus,
I just bought Asus RT-AC5300 and I am not an expert but I have OK knowledge of router setup.
I have couple of questions, any help will be much appreciated.


My setup:
Here is my current setup (please see images below)

1. I am using Adaptive QOS
   1. PS4 has highest priority (connected with LAN port)
   2. My laptop and TV has medium priority
   3. All mobiles and tabs have lowest priority
2. I have latest Asus firmware on router
3. I have DHCP server is set to manual assignment
4. My location is India

Questions and ISSUES:
(please see attached images below, they will help understand my issues/setup)

1. Client List is not stable. It sometimes takes a lot of time to display clients which are connected via wifi. Even though 3 clients are connected. It will sometime show 1 or 2 or 3 over a period of 1 minute see attached image
2. BandWidth Monitor:
   1. Does dragging items in list up and down makes a difference? Even though they have prio set. What’s the purpose of sorting items?
   2. Even though I set Qos to game optimization, DO I still need to set prio in bandwidth monitor. How does it work?
3. Is option Respond ICMP Echo (ping) Request from WAN dangerous to turn on ?
   1. One ps4 , I want to open page http://www.whatsmyip.org/ping and test my ping
   2. With this option off , I can’t get ping
   3. Should I keep it on? Is there any other alternative to check ping with this being off ?
4. Port Range syntax: is this port range syntax correct?
   1. PS4 TCP: 3478:3480,80,443,1935
   2. PS4 UDP: 3478:3479
5. Do i need to setup Game Boost WTFast ?? As it supports only limited PS4 games
   
6. Should I put my ps4 in DMZ ?? will it make difference ? I saw few videos which suggest it
7. Asus merlin
   1. Should I Install asus merlin firware. Will it do me any good ?

Please suggest and review my setup and make your kind suggestions.
I want PS4 gaming to have highest priority over everything.

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[Fanee]

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