( EDIT- as some mentioned like Marco1937 , the dials can be further differentiated by the 27 and 33 minute markers )
Here is what i've found so far :
1. Flat 4 dial serif, most likely 2002
- the 4 in the 40 of the seconds subdial is flat , upper part of the 4 is flat and wide
- 'O' in 'oyster' looks to be round
- 'swiss made' is serif
- 27 and 33 minute markers are long
2. Flat 4 dials, ~2003-2005
- the 4 in the 40 of the seconds subdial is flat , upper part of the 4 is flat and wide
- 'O' in 'oyster' looks to be more oval than round
- 'swiss made' is not serif
- 27 and 33 minute markers are long
3. I'll call this Higher E or Upper E , 2003-2005
- The middle line of the E in ROLEX sits just above the midpoint of the letter
- 27 and 33 minute markers are long
- 4 in the 40 of the sec subdial is flat as well but the top part is narrower than on the flat 4 dials
4. Lower E 
2007-2009 :
- The middle line of the E is just below the letter's midpoint
- 27 and 33 minute markers are short
5. Let's call this one : the Funny E - 2007 :
( i suspect this watch was serviced or something because both dial and hands look like 2002 , dial looks similar to the flat 4 serif one as well.
The case is indeed a 2007 m serial on this example )
- the line sits lower as well but the whole font looks different
- 27 and 33 min markers are long now
- 'swiss made' is serif
6. FAT 'O' dials ~2010-2015:
- 'O' is "OYSTER' looks fat / rounded
- 27 and 33 min markers are long
- Rolex coronet has a bigger hole / more rouned as well
7. FAT 'O' short ticks ~2015 :
- same as the regular fat 'O' dials but the 27 and 33 min markers are short this time
8. APH dials ~2010-2015
- APH letters of the 'cosmograph' word are a bit separated from the rest of the word
- 'O' in 'Oyster' looks like a 0
- 27 and 33 minute markers are short
Diffrences between the 'higher E', 'lower E' and the 'funny E' :
