The reason that seatguru lists the first row of economy as "better" is because it is a "bulkhead" row, which usually means you some more legroom in front, and not having a seat in front of you that could recline. The other economy comfort rows will have extra legroom as well. Seatguru isn't implying the other two aren't good, only suggesting the first row may be the best of the three rows. How long is that flight, maybe 2 hours? EC seats will cost extra, but probably only $29 on this flight. I would select EC if it's available; a little more space for taller people, first off the plane after F. IIRC the bulkhead is not actually a wall on this plane; also, aren't the overhead bins on the left side a bit smaller?