Most people I've spoken to seem very happy with their Carcoon. The main downside seems to be having to deflate/inflate everytime you wish to use it - but of course its this aspect that allows the air to circulate and doesn't scratch the bodywork. If you need an alternative, you could try and an air chamber which is a fixed structure (but this depends on how much space you've got). If you're after a budget alternative, maybe look into a decent dehumidifier?