I was trying to post the following in a topic regarding model RR scale choices but got a data base error message. Here it is:
N: Pros: more train per room area, longer trains, more scenery etc.
N: Cons: Less detail (generally) than larger scales, less selection than HO but still good. Hard on 40 or 50+ year old eyes!
HO: Pros: best variety out of all scales for types of rolling stock available, still able to fit into a good sized room or basement/garage. Excellent detail on many models.
HO: Cons: Can’t fit as much in to a room, especially if you have only a tiny space. Less scenery to train ratio, but still good.
O: Pros: Freaking huge and hefty! More detail. Able to fit a layout in a large basement or barn!
O: Cons: Not very much variety in rolling stock. Expensive.
G: Pros: Well, kind of cool, especially if you have a Christmas tree or live in California or Florida!
G: Cons: Really to big and not enough variety to make a serious attempt at modeling a real RR.