Freedom is a basic 'given' in any true democracy and something to be protected at any cost. Any erosion of our rights and freedoms moves us toward a totalitarian dictatorship where ultimately we are told what to do by the centralised authority, either an individual or a power group. In our system it is understood that our MPs are elected to represent us in Parliament and so they hold surgeries to find out what we want from them. Changing sides does not in any way change their ability to do that effectively. What it does change is their obligation to support their party on the major issues of the day. Usually they all pull together when necessary, especially if the issue is an important one, and we get a result which is accepted by the majority in the house, there will always be some dissenters but by and large the system works. I don't think we should feel in any way unhappy with an MP who votes against his party when he feels it important enough to do that. I would much rather have an MP of integrity and honesty who will do that than one who always pulls his forelock and does what he is told.
And yes, I recognise that honesty and integrity are thin on the ground these days, I was just daydreaming for a moment...………………...