Pros
When I was employed my contract stipulated that I be paid for the work that is completed. This created an exciting and productive environment for me to determine my own salary based on my effort put in. The incentives were great, and I managed to book out more than 200hrs work for many months giving me a healthy payout. The management of the company DO NOT micro manage, and this was a massive selling point for me. One is expected to treat there work environment as a franchise of the business, making it their own, but within the company guidelines. Generally, my experience with upper, middle and floor level management was one of a sort of "caring professionalism", which is somewhat rare to find these days.
Cons
Every company has months where the work flow slows down. Due to the nature of my pay per job contract this heavily impacted on my monthly earnings. This can however be combated through averaging and saving.