Oh, in that case. Yes. I use the COD4 mod tools, Hammer Editor and in house development tools at work. I've got the UDK for Unreal Engine 3 that I mess with from time to time, but that is a much more artist friendly set of tools than anything else. Plus, it takes me a long time to get a complex mesh setup with pretty UV's. Most of my time is spent getting rid of bad stretching. GTKRadiant is something I go back to from time to time at home, but its hard to enjoy because it just isn't as well setup as Hammer or the COD tools when it comes to working fast and efficiently. It needs quite a few things to get to that point. None of those being a light preview. I don't even care about that anymore. Alt drag from CoDRadiantA keyboard shortcut for rotate on axis. Plus the keyboard shortcuts for locking on X, Y, and Z respectively. It takes a bit of extra time to go up to a toolbar to click these thingsRotation and translation Gizmos in all new versions, not just 1.5.0Hide unselected, instead of trying to work in RegionsZ axis cubic clipMeasuring tape clip line. (Place points similar to the clipping tool. Except it draws a line and tells you that distance in radiant units.)Some sort of support for model preview in the file dialogue. (CoD tools does this with a special folder that contains jpegs by the same name as the models. If the support for that feature were there, than the modders themselves could do the rest.)More convenient control and drive scheme for the 3D window, not requiring you to move your left hand from that side of the keyboard.