If you want to try them out, I'd recommend a few shades of cold and warm gray. ^^ Grayscale is fun and gives you an impression of how copics work. ^^ And they are a tad expensive, so you don''t want to dive in without having tried them out.
Thanks, I currently have gray prismacolor markers and I am curious how they fare against copics. I have been wanting to get a set of copics for years because I love markers but just have not found the right fit for me yet as Prismacolor's (when I was using them back in the day) didn't have as much variation in the colors as copics. I also hear copics are better for blending and I really love all the pastel high key colors I've seen in copics.