Should proportional representation be introduced for elections to the House of Commons?

Introduction

The House of Commons is currently elected using FPTP, both political parties wish to retain this pluraluity system, however the Liberal Democrats wish to switch to a more proportioanl system of voting, such as AV+ or STV. Their argument for the move, as laid out in their 2010 referendum campaign included many of the following points:

For

• The House of Commons (and so the governing party) will be made more representative of how the country voted
• A more proportional system would eradicate many of the problems associated with FPTP, such as safe and marginal seats, tactical voting, unrepresentative governments etc
• If people feel that their vote really counts in the overall election, they'll be much more likely to vote
• Smaller parties, which are "squeezed" under the current system, will…