I got 50 for $10 delivered...
Mine showed a light positive at 10DPO.
The First Response barley showed at 14 DPO.
So for me, mine picked up the pregnancy waaaay early.
I recommend getting them if you want to POAS everyday from ovulation. Just have some FR for 'confirmation' before heading to your Doctor, as you are likely not to show on the Dr's test, if you don't show on the FR (my experience anyhow).