Well, I dont have experience with other editors, but I think that my experience with cartography shop says its not worth the money for what it provides.
The documentation sucks and all it can handle is basic shapes. The interface is simple enough, until you try to do selection of objects in a level containing anything above twenty basic elements.
I tried putting textures into the textures folder and the program crashes if you have too many textures there. I have not found a way to rotate objects in anything other than 45 degree angles.
I think that you should ask the veterans here what they use. Judging from the discussions on the forum, nobody seams to be bothering with cartography shop. You can have my licence if you want, I'd gladly sell it to you as I have not actualy produced any work using it. I dont know if the author allows this though.