I would not recommend a furminator for anyone without lots of experience grooming rabbits. I have read many firsthand accounts of rabbits skin being torn by these. Even for experienced groomers, great care needs to be taken when using them on rabbits(if they should even be used at all), especially over the spine and hip area where the bones are not as fleshed over to protect them. I find a damp hand works the best in safely removing molting fur.
I've also heard the zoom groom recommended by other rabbit owners, but haven't tried it yet.