Sure i can share some of something in terms of deep throat.
So far I have tried 2 ladies who do DT in my experience,
1. Kiki - PE Kingland Apt.
her ability to deep throat almost all the way down to my balls, she kept doing DT and sucking on the head for good 15 mins non-stop. That was pretty amazing! she made no gagging sound and wasn't sloppy at all, if you are looking for that you might a little disappointed at this. and she was not allow me to place my hand on the top of her head, I was thinking to give a slight push her head down a little bit but failed to do so. She allow CIM.
2. Sammi - CWB Phoenix Apt.
She has better DT skill than Kiki I would say. She gave me blow job straight after shower, she went all the way down to the balls and I can push her a little down to my balls, it was so good! after a few mins DT action in the bathroom. We moved to the Bed, she just kept deep sucking on my dick, i asked her to give me a few balls deep action and she just go all the way down with a little gagging, so if you like gagging sound, you must her at least once. she also do some sloppy blowjob but not very heavy.
Hope you guys like this sharing