It won't keep perfect time no matter what the hairspring is made of. Saying is..."if you have to have the right time, get a Timex, if you want class, get a Rolex." You can pay less than $30 and get a watch that will keep, virtually, impeccable time and it will last for 5 to 10 years with just a battery change each year. If you keep a $5,000. Rolex for 10 years, doubtless you would have spent another $400 - $600 sometime in that range for a service.
I have a Timex Ironman that is more than 15 years old and it takes a battery each year. Still keeps pretty good time and is waterproof everywhere I go.