I make my own gummy edibles. But, I use dry ice kief to make my edibles. And I use a high THC buds to get that kief, over 20%. I have not yet been able to make a single gummy at 50mg. When testing, the best I have gotten was about 27% per gummy. And the gummy size is your standard 1" gummy bear mold. Obviously I could increase the size and make them more powerful, but for general use, I typically like to have more total gummys than power. 2 of these bad boys will take you a long way!
I only make my own because I am legally allowed to do so from seed > product. If you can't grow your own, it'd be difficult to judge how potent your end result will be!