The real argument to consider is a seniority based system versus a GLOBALIZED system. If a system is globalized, it does not matter whether it is AOS, Navtek, Carmen, or Smartpref. The pilots of Continental have a globalized system.
Although Continental pilots have few PBS rules, which contribute to the dissatisfaction level, the GLOBLIZATION is also a major factor in that it allows the software to ignore the desires of the crewmember so that it may assign the pairings that it needs to assign to achieve certain goals. In simple terms, there may be a specific pairing that may be available to a crewmember that the crewmember has bid. However, if the software determines that it needs that pairing elsewhere, then the crewmember will be denied that specific pairing and another pairing will be assigned that meets the need of the solution that the software is trying to achieve. There is little transparency and no predictability for the crewmember.
Flightline's Prefbid is the only seniority based system without GLOBALIZATION. If a crewmember bids for a specific pairing, and it is available to the crewmember, it will be awarded so long as it does not conflict with a pre-assigned pairing or other pre-assigned activity, and there are no other legality issues such as block buffers, FAR violations, and the awarding does not exceed the wide credit window. Of all the systems, it honors seniority to the greatest extent.
In a globalized system there is the potential that every pilot bidding can be affected by the globalization process. In a globalized system, the software seeks solutions that can basically ignore crewmember requests to the degree necessary to obtain a satisfactory solution, depending on staffing and the number of hours that need to be covered. The goal is for the software to assign the time on every available pilot's line driving toward a solution with very little or no open time and also to drive most all pilots to an average line value. Normally, the credit windows are very narrow to assist in achieving this goal. Some have called it socialization of the schedules.
In summary, individual pilots will get greater schedule satisfaction from a seniority based system. If a crewmember bids correctly, and with a wide credit window, the crewmember will get better schedule satisfaction in both the specific types of trips he desires, and also the line value ($) that he chooses that determines his pay. In a GLOBALIZED system, the crewmember will lose control over specific trips that may be available to him, and in addition, he can lose control over the line value that he would like awarded to achieve desired pay.
As pilots, we strive to control our environment to the greatest extent possible. It is a common thread that we all share. So, why would we not want a schedule bidding system that gives us the most authority possible to control one of the most important elements in our job--Our Schedules! Globalization greatly diminishes that ability for a pilot to control his schedule. Ask any Contiental pilot.
Flightline's Prefbid, a seniority based awarding system, gives the crewmember the greatest amount of control over two of the most important parts of his job--the Schedule and his pay. Most pilots would want a system that grants them the ability to have the most control over their schedule and their pay.