AdGem is truly a gem. So far, they are the offerwall that works best for me and most users around. You will often find here some great offers, so make sure to check them daily. Their support is great and respond quickly, no one I have heard had any issue with them so far. Actually the offers I do with them always seem to get through in the first try, so it is not likely that you will need to even contact them. So if you have found a great offer on AdGem, do not be afraid to actually invest in an offer if needed - you can be 99% sure you will be paid if you follow their instructions closely.