I have a marble slab and a marble rolling pin that SIL gave me in 1983. Slab used to have feet, but those are long gone. Yes, marble is heavy, but it's not so heavy that I can't comfortably use it. Picking up the slab is far harder then using the rolling pin! I use mine for pie dough, biscuits, and cookies. I bought the bands of different thicknesses a few years ago, but they didn't work too well for me, as my rolling pin isn't that long, and the bands reduce the useable width even more, so they just sit in the drawer. I can eyeball thickness well enough that they were a fun item to try, not a necessity.
What I would change is I could fine one I could afford - is to get a larger slab. I use 10" pie dishes, and when rolling the crust very thin, it tends to run off the far side of the slab. With cookies and biscuits that isn't such a problem, as I can do it in smaller bits, but pie crust needs to be all one piece...