A Slicker brush is great for some rabbits. Rex and Mini Rex generally shouldn't be subjected to that kind of treatment as it has been shown on a number of occaisions to damage their fur. Not a huge problem if you don't ever plan on showing or anything, but still, something to consider. And there are still those who show that will use a slicker brush anyway.
I know that for the most part, the shorter the hair on the rabbit, the easier it is to remove it with just a damp (note: not a sopping wet hand) hand brushing over the coat.
I believe that a first shedding will take a bit longer (the shedding of the junior coat) but after that, it depends on what time of year, and the temperature differences between seasons.
Hopefully Rusty will get over his shedding soon!
With our rabbits (mini rex) we've found that they shed more in the fall than they do in the spring, and even still, they don't shed that much. It's nice with the mini rex, because usually just a lot of petting takes away the excess fur.