I don't think there is such a think as good and cheap when it comes to
screen protectors. You can choose one or the other. Personally, I can't even contemplate using a cheap
protector. The expensive ones don't distort the color at all, can last for years instead of months, drastically reduce glare on the
screen, and provide a better writing surface. Since they last a long time, you really don't have to buy a 3 pack. You can get just one for pretty cheap
here
You really do get what you pay for with the expensive ones.