I am no Holiday Inn Express expert, as this is my first time messing with river bed gravel
I collected my river bed gravel in a 1.5 gallon mayo container. I rinsed it out in a 6 gallon tall bucket with the garden hose. If you compare this to rinsing old Eco Complete, most of this new RBG would get suspended in the bucket from the current. It just has much less mass to it.
And nope I don't do the Sara method of replanting yanking up the entire root stock. I always just use a fairly sharp knife to cut the creeping roots around the stem and carefully pull up slowly as to not disturb the lower substrate layers. The old roots are low in the substrate and will break down in time and there is enough of a giant root ball down there to keep things from going anerobic.
My biggest peeve is the old organics dying off of the rock pores showing up on top of the substrate. This is really not a beginner substrate to play with.