I saw that someone posted a comment on how our 900's are 30% more fuel efficient than the 175...this is true.
Restifo came into our training class and proved it, not to mention we had a couple ground instructors that used to fly 175's and they said the 900 blows it out of the water...
The fact is the 900 and 175 have the same engines...
NWA got the 900 cause it is faster and more efficient
NWA got the 175 cause it has a higher payload and is more comfortable...mainly why we don't fly to Mexico or Florida