OpenWrt vs DDWrt
Dec 2020 update: still all-in with OpenWRT, everything works beautiful.
Overall, OpenWRT if you really want flexibility. I dumped DD-WRT (WRT54G) for OpenWRT (ASUS WL-500gP) because of this (related to this), haven't had a regretful moment yet. Not even close.
- reliability – I am not aware that one is significantly more reliable than the other. Both have quite lengthy release cycles, which have yet another bunch of users complaining.
- performance – I'm pretty certain it mostly depends on the hardware device and best compatible drivers most of all.
- configurability – OpenWRT package management system should win easily here.
- ease of use – I liked DD-WRT web UI, I don't have a particular problem with LuCI either. LuCI just got bumped to 0.10 branch in 10.03.1-rc5, which is another step up. But overall I'm definitely loving OpenWRT's /etc. Things in there make sense when you need them to.
- support/docs – Both have phpBB forums with significant traffic.
OpenWRT all the way. Reasons:
- complete control
- modularity
- well organized
Given these parameters, you can judge the coding is in good hands. I am a developer, and I find OpenWRT very modular, very organized, with no limitations imposed. I can pick the modules I like, there are so many available. I can write an application straight in C or C++ and make it work under OpenWRT. I can change the device driver code to suit my needs.
And the whole procedure is documented well enough. Even if you are not a developer, you will find the modular approach in defining your system, stunning. A job well done by the OpenWRT team. And yes, I have used DD-WRT before using OpenWRT.
I might add another category (or subcategory) to the main questions:
upgradeability/up-to-dateness - Has the core 3rd party router firmware been updated "fairly" recently??
DD-WRT; While the widely referred-to Peacock Thread-FAQ and DD-WRT forums predominantly suggest sticking to routers' most stable versions, these firmware versions are with few exceptions over a half-dozen years old! DD-WRT updates are found in the Beta router firmware links organized by year, but it can be surprisingly difficult to find out which exact up-to-date upgrade one really needs :/
OpenWrt; The webpage downloads dot openwrt dot org shows last month's release of Chaos Calmer 15.05, so certainly the OpenWrt firmware is extremely up-to-date.
Tomato; The stock Tomato router firmware listed at polarcloud dot com's firmware link is currently at version 1.28.... from about five years ago! Sure, there are also a bunch of more updated Tomato firmware distribution variations (a.k.a. modifications or "mods") for various routers listed around, but many people either don't know about these mods or if they even work right!