Nearly all 14 SEER air conditioners are the same in the terms of longevity and reliability depending mostly on installation of the system.

14 SEER is for the most part bottom of the heap or entry point system as this is the minimum efficiency rating for those who live in the southern regions of the USA.

The contractor you choose is typically the most important piece to the puzzle, because if problems develop your relationship with your chosen contractor will be put to the test.

Don't buy a HVAC system for the sole reason of it being cheaper than everyone else.

As an example: I have installed generic brands of 14 SEER rating... years ago for a number of people in Katy, Texas. I haven't been back since... not even for a maintenance check.

Installation is everything.