I noticed none of the guys answered which racer, Northern or Southern black, is better. I have never kept a racer(though I still have a strong urge to actually try and see some in the wild here in the US), but I say to go with a Northern black racer.
Thing is, because in many places throughout their native range, northern blacks encounter more rodents and birds rather than lizards in the wild. Southerns, on the other hand, live in the Southeastern US, where their favorite prey is lizards and much more restricted to them.
What I am trying to say is that northerns would probably make better pets because they'd probably accept rodents better than southerns, which usually require scenting the rodents to switch them to a rodent diet.
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Scott
Reptiles
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1 Colombian Rainbow Boa (Rocky)
1.0 Ball Python (Sultan)
0.1 California Kingsnake (Leota)
1.0 Eastern Painted Turtle (Yugi)
0.1 Red/Gold Bearded Dragon* (Irwin, R.I.P.)
Other
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1.0 Betta Fish (Tyrone)
1.0 Hooded Rat (Clubber)