One or Two
Go for one mistress for two hours. That will give a more relaxed session, especially if she does a pre-session interview with you. It also takes time to tie you down - with a two hour session, there is then plenty of tickling time for the mistress to learn your tickle spots, reactions, etc, and get the best results. From past experience, the first session is always a get-acquainted session, so a bit more time with one mistress gives a better result for you. In past double Mistress sessions, I have found that it is good - a lot of sensory overload and all, but it can be a crowd, so to speak, if they are not tickling you in a co-ordinated way. It provides too much distraction, especially if it your first time. Hope that helps.