I have tried RAD platforms for automation of work flows couple of years back. Its good for quick roll outs for light weight apps, anything complex or heavily engineered processes will bring its own sweet challenges. How ever my this experience is based on my three year back executions, off-lately RAD platforms have evolved covering few of the gaps if not all.
RAD was very popular about 10 years ago, now agile seems to be the development process of choice, however, if security is not being considered from the planning stage and throughout the development process, you will have lots of issues with the application when it gets into production. I have seen it too may times.