I may be a mobile phone rather than pay attention to, often have scratches, this is probably related to the use of habits.
Personal experience is, do not stick film about 4-6 months does not spend, after the words, scratches will make demanding people very uncomfortable.
Foil, a film about 1-3 months, after the words, scratches are also very uncomfortable.
It doesn't matter who may be demanding, but all the gorilla glass phones I've used in seven years, none of them have been able to maintain no scratches without sticking to the film. Some people say that there is no scratch, I do not know the situation, because the real use of mobile phone very care is very careful or because scratches do not pay attention to think not, this is difficult to say.
If 3 months to change the film, for most people can accept, dozens of dollars, if 6 months for a screen, for many people is still relatively difficult to accept, even if Taobao goods to 400-500 this is still their own hands, the official price is much higher.
So sticking to the film is still a matter of money. Money is not a problem, the screen change screen, the change machine. No money for a screen change the film is theoretically more excellent solution. It is impossible to give advice to everyone when money is uncertain.
Of course if you intend to change the machine to stop using, then no film does not matter, after all, in its life cycle will not scratch to use, so I will encourage you to change the machine in the first 6 months will be torn off the membrane. For now, if the mobile phone with a year: the more common way is the first membrane three months, the second membrane three months, tear off the film for six months, and then can be changed machine.