Pros
working for post office gives you chance to meet and engage with many members of the local community, it is still looked on by many as a vital service and you do get to feel your helping make a difference in some small way to their lives. also post office do offer a reasonably good pay and conditions package in comparison with the banking/financial branch network and do have many family friendly employment policies too.
Cons
like most companies out there post office is feeling the effects of the changing marketplace and the need to find ways to remain (or indeed become) profitable . this means that there are currently changes to the whole network on a unprecedented scale and obviously this does as a consequence create a sense of uncertainty and concern over jobs. but i try to be pragmatic about it and i believe that if management successfully put the company on a strong financial footing then in the long term it provides beter job security for everyone. so yes its still a company to consider working for.