Hi Craig

It can be done

Here is a video of a twin pulse jet RC model flown in Scotland last year. http://www.youtube.com/watch?v=1e-Ar7gb4tQ

A guy called Roy Levers had a 4 pulse jet Vulcan in the UK many years ago. It was flown but rarely with all 4 running.

A dutchman called Joe Koullen was also on the show circuit for a while with some RC pulse jets in deltas.