Answered by Shaykh Faraz Rabbani
According to the following site any salah done while wearing a watch with a metallic band should be repeated? Is this true?http://www.islamicacademy.org/html/Fatwa/English/Namaz%20in%20
Walaikum assalam,
Fatwas are often bound by the times and places they were given in, unlike primary texts, or even the general rulings of a madhhab. As such, when times and places change, fatwas change.
The scholars I know do not say that it is impermissible to wear metallic watches, whether inside or outside of prayer. (The Question returns to whether they are jewelry or adornment. In our times, they aren’t.)
And Allah knows best.
Wassalam,
Faraz Rabbani