ok i ve taken 2 bottles of epistane 2 years ago and when i opened bottles they smelt like rotten eggs the sulfer smell..i just opened one that ive had for 2 years and no smell at all. Is it still good to take? ive been told epistane can last a few years unopened but this bottle doesnt have any rotten egg smell. no smell at all. should i not take it or is it still good???