An informative Ebay article describes the sizes as follows. "Collectors use common terms, most coined from the Breyer company, to describe sizes of model horses. Traditional is the largest size and typically measures 8-10 inches tall. Classic is the next size down, and measures around 6 to 8 inches tall. Little Bits, Paddock Pals, and Stone Chips size is another size down; it is also called "Curio Cabinet" size, and typically measures 4 inches tall or so. "Stablemate" size comes from the Breyer company and is used to describe horse models at 3 inches tall. Candace Liddy, a famous equine sculptor and model horse creator, coined both "Bantams" (two inch tall models) and Micro Minis, models standing just one inch tall. While some horse models are larger than Traditional size, so far we haven't found anything smaller than micro mini!"
I am most familiar with the Traditional size 8 - 10 inches tall. The Classic Size 6 to 8 inches tall and the Stable Mate size 3" tall. In my future articles these are the sizes I will talk about the most. But no matter the size, breed, color, each model horse has something wonderful to offer the horse enthusiast.