I like that they can be used with any language (C# or Java).
They also support multiple databases such as MySQL & SQL Server which is great when working in an environment where there may not always just one database available! There could definitely do better at making it easier/quicker to create new connectors but this isn't too big of deal once created since its very simple if anything needs tweaking afterwards anyway :) We use them mainly due to their ease-of development compared other tools out there e.g., AWS Lambda functions etc..