As you said, these are generally reliable. Bank credit card centers sometimes do set up stalls in places with high traffic to handle credit cards, and the speed is relatively fast.

the salesman gives the form with complete information to the supervisor on the same day, and the supervisor scans or delivers it directly to the headquarters. This is done on the same day or the next day, and there are special channels to reach the headquarters, so it is fast.

the bank counter only sends it every few days, which is not as fast as the salesman. Moreover, the card handled by the salesman is a door-to-door card, and you can fill in the code of the door-to-door card. Door-to-door means that a salesman has visited the unit on the spot, which is easier to approve the card.

If you feel uneasy, you can apply at the bank counter. It's all the same.