The best thing about this product in my opinion would be the ease to use for both developers and non developer users alike which makes using foundationdb even more attractive than other products out there! I have not seen any downsides so far that i can think off but if you are looking at something like NoSQL then maybe try some others too since they all do different things well or bad depending upon your needs/requirements etc.. If anyone has used this before please comment what their experience was? We were able to create our own customised databases within minutes without having much knowledge required from us (non dev) just by reading through documentation provided online easily accessible via links given below - https://www.foundationrdbms.com/.