When I download software I use download.com & first read the user reviews of the program before I make a decision as to download the program or not. Are there any sites like this that has a rating system or lets you read about other users opinions on the plug-in before we download it.
You can get an idea of what others are saying about WP plugins here: http://wordpress.org/extend/plugins/
http://wp-plugins.net/ is a good place for plugins, they normally always link to the original plugin page, from there you can read comments people have left.