If you can wait and get one at a reptile show. I've been to LLL Reptile, they have 2 stores in California, and they were rude. Their animals were in small enclosures, esp the monitor lizards. I didn't like them at all.
As far as Petco...I bought my first corn from Petco and she is doing great. Alot of folks don't like Petco either. Don't pay attention to anything Petco people say. Most of the time its not good advice and they don't know what they are talking about.
Read all you can before you buy your corn. That way you will know what your getting into and how to care for your new addition. Honestly reptile shows are the place to go to buy reptiles. You can talk to alot of people, different breeders, check out alot of different snakes, reptiles, creepy things. They are so much fun to go to.
I just have those pretty backgrounds you can get at Petsmart or any reptile/fish store. I don't like looking at the wall.
Just my thought on the matter...