1. what about features?
Modular and extensible is the key with MODx, thus the name. That’s not to say there aren’t built in features, just that the core is focused on providing what any feature would need to interact with a site in a centralized manner.
2. what about security? (one of the most important)
We have a very active development team dedicated to making sure your sites are as secure as possible with regard to the MODx software. There have been a few recent security advisories involving MODx, but all were patched and responded to very quickly, and the latest release 0.9.2, includes a plethora of new security enhancements for issues we searched for internally, and found before they could be discovered and reported.
3. weight factor?
MODx prides itself on being a very lightweight system, and this philosophy will be even more evident as the project evolves to the 1.0 release. The primary motivation of the 1.0 code rewrite was to simplify and minimize the core code even more than it is currently, so you will not be disappointed in this regard.
4. ease of use?
MODx is primarily aimed at experienced XHTML/CSS designers, though is also a great tool for getting started in the XHTML/CSS design world. It is also an easy to use PHP application framework that can help you build or integrate PHP scripts into your sites with unprecedented ease, without sacrificing the prized separation of content and presentation.
5. updates/mods etc...
MODx has a very active community and more and more add-ons for both the front-end and back-end manager are available every day. We are also working on a new add-on repository where you can easily find what you are looking for. And once again, changes in 1.0 are going to bring some great new possibilities for installations, upgrades, imports from other systems, and a whole lot more.
It’s easy to extend and add-on to MODx, to make it do what you want it to. That’s one of my favorite things about it.
6. how fast is it working?
In general, in typical environments, MODx renders moderately complex dynamic pages at an average rate of about 2 to 5 pages per second, and can be as quick as 10 to 20 pages per second with full page caching. I haven’t really compared these in laboratory conditions (i.e. as benchmarks to compare with other systems), but I have a feeling it would stand up favorably on performance against just about any other CMS out there.
But, as a Foundation member of the MODx team, and a core developer, I may be a little biased.