Seatguru Delta 737 900 78

Seat guru shows the exit rows as 19 and 20 but delta seat map shows exit rows 20 and 21. Is 30f a seat with leg room? I've looked at seatguru, aerolopa, even delta's website and all of them are outdated versions. Use airplane seat map to find which ones are more comfortable and which should be avoided. For your next delta flight, use this seating chart to get the most comfortable seats, legroom, and recline on.