RUGF can be used sucessfully in planted tanks if the plants are properly choosen. Well designed RUGF's eliminate most of the flaws that condemn UGF's. However, plants that are heavy root feeders or plants that develop a large root system should be avoided.
A planted tank with Anubias, Bolbitus, Java ferns, Java Moss, and most fast growing stem plants will do well and not cause any problems with the RUGF.
Another option for those that are "sold" on the RUGF's efficiency is to "pot" rooted heavy feeding plants like swords. I have a friend from Usenet that have an incredible tank with RUGF and potted swords. Properly setup these tanks can be almost impossible to muck up.
All that being said, I failed at my single attempt at using RUGF on a planted tank...I don't have the discipline to limit the type of plants and to not achieve optimal plant growth.