Advantages

BMP has the following advantages:

• Preserve Canada’s tried, trusted and traditional First-Past-The-Post (FPTP) voting system, where every eligible voter casts a simple ballot to elect one member from their electoral district to represent them in the House of Commons. FPTP is familiar to Canadians and retains direct representation (i.e. one MP per electoral district).
• Improve proportionality of overall parliament, but do so by province and territory, in keeping with the regional nature of the Senate. This means the governing party in the Commons may still get seats in the Senate, for regions in which they are underrepresented.
• Make every vote count: proponents of the status quo like to claim that every vote counts, but what they really mean is that every vote is counted, which is not the same thing. BMP means that your vote is counted towards selecting your MP, but also counts towards balancing Parliament as a whole in proportion to the popular vote.
• No additional costs to government (since there are the same number of representatives) or Elections Canada (since there are no changes to the current electoral method).
• No party lists, which means no unaccountable MPs or party hacks and bagmen in the Senate. Further, Senators will will be more accountable to Canadians, having been selected by them, rather than appointed in Ottawa.
• Address the seemingly intractable Senate “problem” by revitalising it for the twenty-first century. 
• Reduce strategic voting and voter apathy once Canadians understand that their vote will choose Senators even if their preferred Commons candidate is not elected.
• Encourage collaboration and cooperation since the governing party in the Commons will have to reach across the aisle and to the Senate to craft legislation acceptable to both houses. This change will take time, but we expect it to foster more civility in Parliament.
• Flexibility in implementation. While we have tried to keep BMP true to our current Westminster system, in the future it could be adapted; for example, by introducing more complex ballots that allow votes to choose both a Commons candidate and a Senate party.

Disadvantages

BMP is not perfect – but no system is:

• BMP is probably less likely to achieve perfect proportionality, and may not achieve the same level as other systems, such as Mixed-member Proportional (MMP) or Single Transferable Vote (STV).
• BMP will yield more proportional results in the largest provinces (Ontario and Quebec), as the larger number of seats yields more flexibility. This means Canadians in smaller provinces and the territories will see less of an improvement in proportionality. This is because we have implemented BMP by province and territory to be consistent with current Senate regional representation. This approach could be altered but would likely be more difficult to implement.

50:50

There are a few features of BMP that some will see as advantages and others will see as disadvantages:

• BMP retains so-called false majorities in the Commons (i.e. where one party holds more than 50% of the seats, and government, despite winning fewer than 50% of the votes). BMP tempers this by diluting the 100% power that normally flows from a false majority, since the government will have to work with the Senate to craft legislation acceptable to both houses.
• As a result, BMP is likely to retain, or at least continue the high rate of, majority governments, which some see as being more stable.
• BMP retains the Senate. We see the Senate as an essential element of Canada’s bicameral system, and think it can be saved from itself. Many would like to see it abolished, but as the Supreme Court made clear in the Senate Reference, that is all but impossible.