Express entry and PNP are both programs under which prospective applicants apply in order to get permanent residence. Express entry is a federal program and the prospective applicants can evaluate their eligibility and enter pool.
PNP or provincial Nominee programs are designed by provincial governments, by Ministry of Jobs, Economic Development and Competitiveness. The idea is to support the manpower requirement of province and help economic development of the province.
Provincial Nominee Program (PNP) is the Province’s only direct economic immigration tool for bringing in new Immigrants
It provides a pathway to permanent residence for highly skilled, in-demand workers and experienced entrepreneurs, so they can settle in a province and raise their family.
The best answer to the above question would be that there is no comparison, however, it depends on the profile of the candidate and which program will suit his requirements.