thanks for the replies.
Yeah i kinda figured that a negative approach to using these tapes would probably negate the effects, so i usually don't think about whether or not they work for me. Well not at the time of listening to the tapes anyway. But i think my scepticism is mostly centered around the self-esteem supercharger tape at the moment.
Having read what Grant said about the tape maybe i should be saving it for specific situations/events when i actually do feel a need for a boost in self-esteem, as apposed to using it on a regualr basis. I guess i should be making more use of 'new behaviour generator' as it seems like a highly versatile tape.