Lush is amazing! I never know what to buy either, so I ask my friends to buy stuff for birthdays etc and they always pick out great stuff. They smell amazing and I think they kind of beat the body shop!
I haven't tried a Lush hair mask (not even sure if they do one?) but I got a bed head one the other day and oh my god.... get one! They make your hair super duper soft and shiny and when you put it on you can literally feeeel it working on your hair! I absolutely love them :)