I've seen Lucy Lake who was pretty much considered the gold standard when it came to DT skills and she maybe got half way down on me.
It really depends on your size and even erection angle plays a part. Some smaller to average guys pretty much describe all the women they see as having deep throat ability when that really isn't the case. Do some extra research on the recommendations you get.
Hailee in Surrey has crazy oral skills and the last time I checked does CIM as well. I can't say enough about her technique. Smile on my face just writing this.
I just recently saw Lolita in Richmond and she's enthusiastic and orally gifted as well. Lolita is south american and very light skinned. Very tall though if that's not your thing. 5'10"