Pros

Paid for work done rather than hours present, allowing fast workers to finish early.
Minimal intervention from supervisors - prepare route then on your own for 4 hours of walking.
In Alberta 7-8 months of the yr are great beautiful weather, sun is shining and everthing is good with the world. On a good day ( light mail, good weather, good route) you can feel like you have the best job in the world.

Cons

For 4-5 months of the year the job can be hell - 5 hr forced march's through knee-thigh-waist deep snow in -10 -20 -30C or worse weather, falling slipping and jarring become weekly if not more often ocurences, if you get injured during the course of your duties you are made to feel like a pariah, more often than not made to work night shifts in a sorting plant, a process designed to get you back to your normal duties as quickly as possible - often before you have recovered fully - resulting in long term injuries that never fully heal. Especially anoying is the attitude of management that all injuries are avoidable, when this is patently false - some injuries are of course avoidable - adobt best practices, pay due care attention etc but when you are working to a time limit in awful conditons accidents happen.
Currently a very big downside is the proposed restructuring of Canada most operations - no current postal worker knows what lies in their immediate future (ie 2-3 yrs) every job is likely to change or end. This is an amazingly stressful situation as an employee to find yourself in, a situation that is only likely to get worse as time progresses. We all know this is happening but there is no communication from management - no leadership.
If you make an honest mistake - you are given a meeting where you are informed that your job is on the line. Very close to bullying.
The very worse thing about the job is that nobody will ever believe how hard your job can be.
You tell them that 80% of new recruits quit because the job is difficult and they respond with 'but you walk for a living' very frustrating - the public as a whole have a very minimal level of respect for letter carriers.

Advice to Senior Management

Employees are not the enemy, assume that the vast majority of us want to get the job done to the best of our abilities. Lead us - what does the future hold? treat us like adults and perhaps we'll respond in kind.