The choice between metal and plastic frames depends on individual preferences and needs. Metal frames are valued for their durability, classic style, and ease of adjustment. They are often chosen for a sophisticated, professional look. However, plastic frames offer a wider variety of colors and styles, are generally lighter, and can be more comfortable for some wearers. They are also typically more affordable and are favored for making a fashion statement. Ultimately, the decision should be based on factors like comfort, style preference, budget, and lifestyle.