As a clarinetist, I only use these as placeholders or when working late at night, so I don't like to put a lot of time into it when I do. As a result, I haven't gotten to a point where I can safely recommend VSL, as my quick-and-lazy workflow approach prefers Marcato patches and cringes otherwise. But they may well be as good as the VSL Flutes, given more effort.
Although I sold it in order to force myself to stop procrastinating on recording final live parts, the Audio Modeling Clarinets are mind-blowingly good and hyper-realistic -- at least for non-classical work (I didn't bother trying them for classical-style pieces as those will automatically get my own live playing). It is a shame though, that they don't cover more voicings than they do.
The new one from CMusic sounds very eastern to me, and is a bit tempting just for working in those genres and getting some placeholder parts that serve as a reference for me to fine-tune my own playing to better match the style and timbre needed by Klezmer, Balkan, Roma, etc. It might be good for classical as well, but their audio demos impress me the most in the genre stuff.
I have a policy of not saying anything bad about ones I've sold, out of respect for the developers, but for developers that don't allow resale, I go through a big debate with myself about whether it's OK to say anything negative or not. So I'll just say that the one that appears to have the most coverage of voicings throughout the Clarinet family, is the one from Neocymatics. I've had no success yet though.
Also, lest it seem to be inferred by omission, that I think the one from Embertone is trash, I do think it is very well done, but I am super-picky about clarinet timbre, and absolutely despise some of the most famous players out there (living and dead, e.g. Sabina Meyer), with a strong preference for a much warmer tone overall (e.g. Emma Johnson). I am especially fond of many of the English and San Francisco players, but have always disliked the ones from New York and Philadelphia. I respect them, but simply dislike their timbre. So that is the biggest factor for me, and affects my rankings.