I've had a chance now to use the DevExpress and Telerik control suites. Here are some observations which may be helpful to those of you in the market for controls.
DevExpress wins this hands down. They have a single installer for all products. You can select only the components your licensed for or trial those you don't own. The installer also updates existing products, so no uninstall reinstall dance.
Code Rush beats Telerik Just Code. There is simply no comparison in the functionality between the two products. It's like comparing an Erector set to Lincoln logs (I may have dated myself).
Telerik seems to update like a person with ADHD. Every product has an update at a different time. This is a pain in the backside. Additionally, the highly touted visual studio extensions require you to run Visual Studio 2010 as an Admin to update, and then they fail with a "Program must be removed from Add/Remove Programs", major fail Telerik. DevExpress as mentioned earlier provides a unified update process which is easier to manage.
In this area both vendors are pretty evenly matched in functionality. I've found the DevExpress components to be more "Developer Friendly" in that they work as advertised and don't require any fiddling to get the components to work. As an example I created web applications with grids that rendered a set of image records that were retrieved as binary images from a simple database. The DevExpress Binary Image Column rendered right out of the box, I could never get the Telerik Binary Image column to display anything other than an "X". If it's documented somewhere I sure wasn't able to find it.
I have had to use the DevExpress support and they are an outstanding group who addressed my issue in a timely and efficient manner. I cannot comment on the Telerik support as I haven't opened any issues with them at this time. The DevExpress issue was a help installation issue on Windows 2008, which was addressed and resolved in less than 48 hours. Pretty impressive in my opinion.