I tend to use a 1K synthetic stone to set the bevel then go to a coticule. Getting the best out of a coticule is approaching alchemy, getting a decent shave ain't too hard.
I've heard some assign different grits numbers to different coticules, I've heard others say a top notch shave is achievable from almost any coticule providing you adapt to the stone. If you are intrigued by them buy one and play around with it, if you don't like it it shouldn't cost you much as they hold their value fairly well. They have been used by people who like sharp things for a very long time, there is a wealth of info on them online and there are a lot of fans willing to help you get he best from them. http://www.artisanshaving.org"]Artisan Shaving seems to be where many of the Coticule.be forum contributors went when the coticule.be board closed.