HPC - CodeMax: How much is it in the US?

It may be a good machine but the idea of suing over the letter I read is ridiculous.

What has that to do with you filing a number of nuisance suits over a simple letter stating dissatisfaction with your product?

The fact is, you, through your actions have helped the original complainant reach far more people and do far more damage to your reputation than would ever have otherwise occurred. Had you simply stated the case for your machine and that the criticism wasn't deserved (In your opinion) the situation would be long forgotten but instead you choose to remind everyone periodically of the individuals dissatisfaction (to put it mildly) with your product as well as your customer service. Not to mention the fact that you sue your customers for politely stating their negative opinions of your product.