When you enter into any paint store or hardware store looking for a roller cover you’ll encounter a wide array of options. You may think price doesn’t matter and just go with the cheapest option. However, price does matter, typically the more expensive the roller the higher the quality of the roller. If you go the cheaper route it will cause more issues while working. With a cheaper roller cover you will get debris and loose naps on to your paint finish. With cheaper rollers the nap tends to not stay attached to the rollers core and ends up in your finish. When selecting a roller cover their are two types. Foam roller and nap rollers. Foam rollers are good for leaving a thin layer of paint on the substrate. Best used on ultra smooth surface and used with latex based paints. Cheaper foam rollers will leave little craters all over your project so when selecting a foam roller you will want to go with a high density (typically more expensive) foam roller. As for nap rollers you will want to go with a roller with synthetic naps or microfiber. Synthetic nap rollers are usually higher quality and the higher the quality the less debris and loose naps will end up on your substrate. Nap rollers come on different lengths 1/4-3/8 nap length are good for smooth-semi smooth surfaces. 3/4 to 1-1/4 nap length are good for tougher surfaces with more texture.