I don't know anyone that's voting in this TA for the signing bonus. I am voting yes because of a number of reasons:

Over 5000/month pay raise (A 2 year F/O gets about 2700/month) (those numbers include the DC plan)
A great LTD plan
A good DC plan
Better Scope

I don't think we'd ever get full retro. And I'm not willing to lose 5000/month to take that chance.