All my hammies are dwarves I just like them being cute fuzzy balls of fur. In the case of robos, a speedy ball of fur.
True, Russians & Winter Whites are hybrids unless you have a pure bred which is very unlikely as they are very uncommon. All pet store hammies are hybrids & prone to diabetes except robos, as stated above.
I wouldn't attempt to keep 2 dwarves together unless you are experienced with dwarf hamsters, just my opinion
