This is my personal experience and opinion only -

#1 - did tea - contractions still didn't get regular so after 2 days of on/off/on/off and exhaustion, put on synto drip/epidural/forceps - yuk

#2 - did tea, waters broke, no contractions after 36 hours still, synto drip - birth ok

#3 - took raspberry leaf tincture instead of tea that my acupuncturist made for me - waters broke, contractions didn't start for 24 hours (must be my body) - and when they did they were absolutely text book with a 6 hour labour from start to finish and a beautiful birth ...

So in my opinion, the tincture was the best - regulated dose - easy to take, and distilled pure leaf so more natural (but it is distilled in vodka LOL but the amount you have of course is like 2 drops) I started on the tincture a around 36 weeks - increased daily dosage every week, acpuncture at 38 weeks and same day my waters broke!!.