shedding products, safe? effective?

Morning Everyone!
I was wondering if anyone had ever used Shed-Stop, or any of the other products to help prevent everything from turning into one gigantic furball??? Are they effective??
Do they work?? Most importantly are they safe??
I have four cats and they have been shedding since I moved last fall. I thought it might have been the move at first, but it still hasn't decreased and now the actual shedding season has begun!
They are all indoor cats and I do brush two of them several times a day,(the other two when they are in the mood) but it just doesn't seem to make any difference.
I will be moving again (topic of another question later) and would like to try to get this situation somewhat under control before going and turning somewhere new into something with a permanent fur coating!
thanks for any ideas!
'the furry mommy'