Leaving threads about bad workmanship, pathetic time delays ( read TB's SGD threads - they're mind boggling ) and other shenanningans is only right. This is meant to be a community, and communities generally like to look after each other.
By all means remove trolling posts and openly slanderous ( or is it libel - i get the 2 mixed up ) but in the main, genuine grievances should stay as a warning to the community. As per mr Wave's thread. So i guess internet feedback specifically posted on close communities is a good thing, and long may it continue.
As long as what anybody posts is true, and can be proved if being legally questioned, then there is no issue, legally or morally
Bad workmanship or business practices should be highlighted in every walk of life, whether it be basses, carpenters, builders, plumbers et al