Scott, It's all of the above for fabrics. If you can tell me what type you are looking for, I can guide you into the best deal.
The most common cheapie is the horizontal mini blind. Usually the most common thing to go is the lift cords, they get eroded by the sun when the blind is down and then jammed in the roller or claw in the up position. Second is the ladder that supports the slats. I had lunch at a Chili's today and that was the problem with every blind that I saw in the place. Aluminum slats have sharp edges that abrade all of the cordage and plastics are heavy and apply more strain to them. My current favorite in horizontals is bamboo. It's mid priced, rigid, fairly light and eco friendly. Notice that I didn't say 'cheap' so they also come with better quality ladders and lift cords.