Do you know why does Rolex use 28 in the date window of the watch, in all ads?

That's because of all numbers between 1 and 31, 28 uses up most of the space available for for the date, so it looks better under the magnified image. 

You need at least one 8 which obviously cannot be the first digit, and of the 1 and 2 which can be the only first digits, 2 again occupies the most space.

So Rolex show up the date which would give the most detail under the cyclops magnifier.

Do you know what is VPH or BPH?

VPH (Vibrations per hour)  and BPH (Beats per hour) is the same thing. VPH(Vibrations per hour) is a common notation for movements in watches today and can greatly help in deciding on the quality of a timepiece. I would share it with my fellows. Basically it breaks down to how many times a watch will tick in an hour, if you hold your mechanical watch to your ear and listen you should hear a rapid "tick-tick-tick-tick-tick-tick", each of these ticks are what counts toward the VPH when calculating the frequency of the watch.
18,000 VPH or 2Hz (Classic manual wind movements)
19,800 VPH or 2.5Hz (Cheaper Chinese movements)
21,600 VPH or 3Hz (Lower frequency for automatics or manual wind)  - Most of the Japan Grade watches are 21600bph
28,800 VPH or 4Hz (Most common automatic movement, can also be speed of a manual-wind) - The best replica watch use Swiss ETA movement which is 28800bph. Original Tudor watches are 28800 bph.
36,000 VPH or 5Hz (Advanced movement, El Primero Zenith - in some Rolexes and TAG Heuers) - Not available in replica
43,200 VPH or 6Hz (Advanced movement, Audemars Piguet ChronoAP)  - Not available in replica
72,000 VPH or 10Hz (Advanced Automatic Movement Rate "Breguet Type XXII")   - Not available in replica. 

Replica Watches Buying Guide – How do I know if the site is legit to buy replica watches?

1, Be sure to check the pictures of the watches. Some site they list original watch images on the site, and no picture of the actual replica watch, DO NOT BUY FROM THEM. Make sure the pictures on their site are actual pictures of the actual replica watch.

2, Ask them a question before you purchase a replica watch. Make sure someone replies with professional answer. First, you can make sure the site is active. Second, you know you are dealing with someone speaks English and professional about watches. If they do not answer you, they may do not know how to answer or even do not speak English. Make sure do not deal with someone that not professional, they can not help you if there is any problem with your watch in the future.

3, We have a lot of customers ask us, how do I know if the site is secure to buy? Actually it is very easy. As long as they take credit card payment, then you are protected. You can always contact your credit card company if you do not receive what you purchased. But be sure do not try to dispute a charge on a delivered product, because this will affect your bank credit in the future. Try to communicate with seller first before you do a charge back.

If all 3 matches, then you can order replica watches from them as long as you like their quality and price.