When it comes to the price, plastic storageware beats glass hands-down. However, that lower price doesn't mean quality. Plastic degrades much quicker over time than glass, especially if you're constantly heating up your leftovers.
Additionally, recent studies have shown that most plastics, even BPA-free ones, can secrete harmful chemicals into your food when heated. With glass, you won't have those risks. In fact, it's the only packaging material that's generally regarded as safe by the FDA.
Next, we have the food-spoilage factor. Since plastic is more porous than glass, food tends to go bad faster in these containers, and that's just more money down the drain. Over time, plastic also tends to absorb the smells and color of food since it's so permeable.
So, while glass may be a bit more costly up front, it's a much better long-term investment. The next time you have to buy storageware, choose this budget- and eco-friendly option.