I asked my midwife about RL and she said the women that have used it in their group practice generally have shorter and more efficient labours. She recommended taking the tablets - apparently for the tea to be effective you have to drinks gallons each day, the tabs are more concentrated, but if you love herbal tea - give it a go!
She said if I haven't started to get tightenings or BH by about 30-33 weeks to start then, but to start about 35-36 weeks if I am already experiencing them.
Lolly