michaelmurfy: I don't think you've justified it and have instead just rushed into it.
Switches are cheap - $30 gets you a 8pt Gigabit switch which will be fine for the job. If you were to get a UniFi or one of the Grandstream access points you'll just need a PoE injector which are around $20 to buy. The wireless on those access points is quite superior than this router can offer (serious here). A Grandstream GWN7610 can cover a 2 story moderate sized house no problems in my testing.
All up - at a cost about half what you paid for a better product. Your current product is currently causing you headaches with configuration and the thing is going forward support won't be quite the same as enterprise grade or small business kit which get updated with new features all the time. Also, these solutions will look nicer than a massive router with multiple antennas poking out.
Furthermore. The UniFi kit can mesh if required if you were to go towards that. Has a far nicer interface, is easy to configure and just works and would be cheaper overall. There are also other solutions such as the Uniquiti AmpliFi which is not only a better and cheaper product but combined with a $30 switch would achieve a better result.
Just saying, you really did get ripped off here in a pretty major way and have not put too much thought into this.
I may agree with you if I have more skills and time. The problem was not just the skills/time/price, I require possibility to return the product IF, if it happened again, that Vodafone does not support this router. About support, Vodafone support can't make the different between external IP address and dynamic local IP, and you are talking about "enterprise grade or small business kit".
I think its too late anyway. I need to test my work VPN connection and see if it drops or not. Thanks for advice, if this router fails, I will follow your suggestion.
PS: Asus interface is really horrible. :(