I've used the SkyWest PBS and the PBS at the airline I was furloughed from prior to SkyWest. I also had the miss pleasure of working hard lines at that employer too. Here are my thoughts:
1) Every PBS places the company needs above the pilot needs. The primary point of PBS is to staff the available flying and if possible take into account the pilot's request. You need to understand its job is to staff the flying at all costs.
2) I was very junior when I went from hard lines to PBS. PBS improved my quality of life most areas. PBS provides flexibility that hard lines do not such as specific days off. I might need every Wednesday off but there would be very few if any hard lines with all Wednesdays off. Even as a junior guy I could usually get them with pbs. Now if I'd asked for Saturdays off I wouldn't have gotten them. PBS did on average give me more days off per month.
3) Hard lines do benefit vacation though. If your pairing touches your vacation you would get that trip dropped.
4) PBS allows more flexibility and also introduced more flexible trip trading.
5) The SkyWest PBS software is much less user friendly and generally not as effective as the one used in my old company. I don't remember the vendor for sure but I think it was a sabre product.
6) Both PBS's worked a similar way when it comes to coverage days. They will flag days as needing coverage and start assigning trips. The difference is the SkyWest system can assign senior guys coverage days then by the time it gets to the last few bidders it may have filled them so the junior guy might get it off. There are so many variables so it is hard to tell if seniority was violated. The other PBS seemed to go to the end of the list and work backwards to fill coverage days. I was never as suspicious as iam of the SkyWest PBS software.
7) Your PBS line is very dependent on staffing. The first company was very understaffed and I pretty much worked 90 hours with 11 days off every month for 2 years. Staffing at SkyWest is much better and I'm more senior in base but even when I was junior I could stay down to 80 hours with around 14 days off. Again this is also very dependent on the pairing construction.
8) Understanding the software logic is key to finding the best quality of life you can hold at your seniority.
On the while pbs is better than hard lines. However if I could switch PBS vendors from the current SkyWest vendor I'd do it in a heart beat.
I hope this helps.
Airfix