I have used them for years. However, the final straw for me is how they're beginning to charge for keyword rank tracking. They say it is to save money on development...however, they are requiring you to move to the cloud and begin paying for the privilege of using the product you originally paid good money for. Sure they have a 'free' plan, but the limits on the number of keywords they'll track for free pretty much excludes any serious internet marketer.
Anyone thinking of using Market Samurai or Article Samurai, consider SEO Moz (SEO Software. Simplified. | SEOmoz) which gives you the same functionality and is already cloud based. No local install. I'm in no way affiliated with SEO Moz, I just discovered them and the product is top notch.
The best way to send a message to companies that start charging after selling you a 'one time fee' product is to stop using them, move to the competition, and hurt them in the pocket book. This is bad business and should be punished with loss of business.