I've been on it for almost 2yrs now and for me it's been a real game changer. Yes, it did take a while for my system to adjust, and I had some odd side effects including inability to tolerate some alcohol (white wine & prosecco), but I had improvements in flushes within days plus libido improvements and reduction in muscle/joint aches.
I was also sensitive to when in the day I took it initially, settling on 2.30pm as the best. This has now moved to 6-7pm as I've added testosterone to the morning (every 3-4 days). It was suggested to me as I have a problem with progesterone causing severe depression.
If you are trying it I'd say allow a minimum 3-6 months trial for everything to settle down (in the absence of serious side effects). What have you got to loose?