Hey everyone,
just purchased one of these beautiful routers tonight, what is the best firmware to use?
Latest Asus firmware? or latest Merlin build?
thanks in advance
I asked a similar question in the Asus-Merlin Firmware portion of this forum but slightly broader in scope. I asked people for their experiences with Asus-Merlin vs. Tomato-Shibby vs. DD-WRT Kong Firmware. Merlin stated succintly that Asus-Merlin was for performance, DD-WRT was for features, Tomato was a combo.
I have run the stock Asus Firmware for about a year. I have run the Asus-Merlin Firmware for about 2 weeks. I find that the Asus-Merlin 374.40 final is as stable as the best stock Asus Firmware. I noticed a slight dip in 5GHz wireless transfer rates going from the older Asus Firmware (before the Netgear suit) to the Asus-Merlin Firmware. I don't recommend using the older stock Asus Firmware because of security issues, but it was high performance on the 5GHz band.
Asus-Merlin Firmware has several advantages over the stock Asus firmware if you play around with your router or need specific features like OpenVPN. If you just want a stable Ethernet LAN and solid 2.4GHz or 5GHz WiFi that you can just "set and forget", the latest stock Asus Firmware will work great for you. I have just aquired another RT-AC66R and some AC adapters to evaluate as improvements to my wireless network. I get slightly better performance numbers with the Asus-Merlin Firmware than what Tim Higgins published for the RT-AC66U router with stock Firmware in the AC band. I have not run the tests enough times to say that it is statistically significant.
The features in the Asus-Merlin Firmware that I really like, and will keep me on Open source Firmware, are the Site Survey feature, Temperature Monitoring feature, and Open VPN. Site Survey allows me to determine what other wireless radios are in my area and tell what channel and sub-channel they are on. Other software such as inSSIDer are available but they work with a PC or Laptop radio, not the radio of the router. I want to know what the radio on the router "sees". The stock Asus Firmware does not have this feature. There are lots of things you can do with this feature if you are interested. I use it all the time when i am testing system upgrades.
Temperature Monitoring is also a open source firmware feature that I find valuable. It allows me to monitor the temperature of both the 2.4GHz radio and the 5GHz radio simultaneously so I can adjust the power output of each radio frequency separately to ensure that I do not exceed the temperature parameter that I have set. Hopefully, this will allow me to ensure long life for the router with maximum radio performance.
Open VPN is a feature that I have read is being implemented on the new stock Asus Firmware for the RT-AC68 router. You can get that right now for the RT-AC66 with open source firmware. If you need to have VPN and you want to implement it through the router, you cannot use stock Asus Firmware today (to my knowledge).
The deciding factor for me to stay with Asus-Merlin over Tomato-Shibby or DD-WRT Kong is that of ease of implementation and stability. I read the other forums where Tomato-Shibby and DD-WRT Kong are discussed. Those indicate that actually loading the firmware can be hit or miss and stability is still an issue with 5GHz AC. That constantly changes but, for now, it isn't worth it to me to sacrifice stability and performance for more features. I am still trying to utilize more of the features that are available to me on the Asus-Merlin Firmware. Having more features will just take more time to learn. In my experience, the most difficult part about putting Asus-Merlin Firmware on my routers was finding the download site and choosing which version to flash on my routers.

That made the decision to switch to Asus-Merlin a "no brainer".
I will say that documentation from Asus and Asus-Merlin is not as complete as I would like. My research indicates that other open source firmware documentation/user manuals are far worse (like non-existant). I have other routers from D-Link, Linksys, and Netgear. They combine poor user manuals with GUI's that are much more difficult to navigate or are so sparse as to cause significant frustration (the new Buffalo 2.13 firmware).
These are just my opinions/observations. This forum has a lot of members who are extremely sophisticated users and can probably give much more information. I am interested in hearing from them as well.