Send application by mail or made in person

[ydependant]

Could someone explain me what the difference between send application by mail or made in person at Public Enquiry Offices (PEO), except of costs?
I heard that it affect on application processing time. Is it?

[cwhnt11]

when you make it in person, it takes 1-2 days but in order to have an in person application, you have to have an appointment. generally appointment dates are very full, you need to book in at least a month earlier.

by post, it takes 6 weeks to 3 months sometimes.

if you have enough time until your visa expires (check the website to book an appointment) and money, apply in person.

[Greenie]

You should only apply in person if your application is straightforward. If it isn't then they will not be able to make a decision on the day and your application will take just as long as if you had applied by post.