I have CA-14 and AT853, and have been trying both from this last summer...
In my experience, there´s very little diference between both, being both excellent...
When I do a double recording using both, both recording are equally good... It´s possible that the AT853 takes a bit more of high frecuency than the CA-14 and could sound a bit sweeter, but I don´t think this necessarily makes it a better recording,... I think is just a question of taste...
I tend to set up the mics in my neck and in this regard, I prefer the CA-14 because the solder of the clips, ...the clips are very solid and I get a very reliable setup... on the contrary, the AT853 doesn´t have their own soldered clips and so I have tryed Schoeps (if I remember well) clips with them, but they don´t fix them to the collar so strongly, and lose the proper orientation easily... in any case, when I´ve tryed other ways of mounting them in the neck, they make the whole thing very bulky, ...not so with the CA-14....
Anyway you could avoid or reduce this issue mounting the AT853 in a hat instead of your neck, if this can be an option for you....