I spent heaps of $$ on OPKs from the shops when we first started TTC but then I tried the ones from the Downunder site that's listed in the BellyBelly Directory. I found that they worked just as well as the ones from the shops but they were much cheaper ($2 each - bargain!!). Fantastic considering I went through so many of them due to irregular cycles! They worked really well too (as you can see from my ticker LOL!!).