Hi, I am on my 3rd cycle of using these (2nd pack). They were great first 2 cycles and I had a positive on day 15 or 16.
This month however I never got a smiley face. I'm not saying this is a problem with they opks as I am off work with stress so could ovulate late or not at all.
I have to say that when they worked, we found it extremely useful to know exactly which days were important. For me they're worth the money as there is no agonising 'is there a line?' moment - it's a clear result!
I suppose it depends how long we are TTC as to whether I'll continue to buy them. They are very expensive so I suppose after a few cycles I'll know my ov date better and might resort to not using them.