Please help understand what is the difference between the 2. I have been looking and bought some 10mUI last week online cus they were cheap being so sensitive...but i notice there is a big price difference in the 2.. Are they different at predicting? is one better than the other?? I really need to know cus i tested 10DPO and got several and did another that seems to have been a midstream one that didnt give on the box what mUI it was but showed ...pleeease let me know...thanks babydust to alll