I met all of them: Bella, Virag and Poppy. I'd put them in this partucular order as DT skill.
Bella DT: no gagging and deep. I felt her mouth and throat like a pussy, very comfortable.
DT Virag: no gagging, very good but tighter throat when I was balls deep.
Poppycock: with gagging, couldn't keep it down the throat for more then few seconds without gag. Tight mouth feeling some teeth and tight throat.
Then 4th position for littlemissElla, although she wasn't able to keep the cock down the throat for long time.