Going to HK to apply for work visa. How long is the processing time?

I saw this above =
Processing Time
It usually takes 4 working days for processing. For example, you submit application on Monday and then you can pick up your visa on Thursday. Additional US$ 30 is charged for 1 working day processing, and US$ 20 for 2-3 working day processing.

So I can go there on Monday and leave on Wednesday if do the 30 or 20 usd additional charge.

Thanks for the help!