The long side without any latch would need reenforcing. That's a lot of unsecured edge for a snake to push out of.
You can drill holes through both edges(lid and tub) and put thumbscrews through to secure it though.
You want to use a smaller enclosure for smaller snakes however. It makes them feel more secure. Check this site for stickies on setting up a tub.
Tubs are preferably by many keepers, because it's easier to keep the humidity proper.
Oh, and don't get the one with wheels. They are more of a pain to clean around the corners.
HOpe this helps, I'm sure someone else will go into more detail!