IMO, you should really think about it and only get one if you're ready to pay for everything it needs, and look after it well. Sorry to sound like someone's mom but you need to know what you're getting into. As sapphire said, feeding can be expensive. Personally, I like garters and ribbons as they are interesting, active, very curious, and their food is very cheap. (Here, feeder fish are 10c each, and slugs and worms are free
) Also the snakes themselves are very inexpensive. But, they don't get very big (around 3f usually), and you said you wanted something not too small. So, just something to think about. Other than that I would recommend corns, and i'm sure many of you agree that they are a great beginner's snake.