So far the LED bulbs I have (maybe four in the house) are well behaved -- one is maybe 5 ft. from my Sangean PR-D5, and it puts out no RFI -- it does have a slight hum that is just audible to the ear, but no RFI.
The others are quiet RFI-wise, also -- and they're not brand names, basically what you get at a box store like Walmart (can't remember the exact store where I got them).