I would try something slightly different. Use a 'Trojan Horse' topic or subject. Email saying you are trying to use the company's product or service in a current project. Ask them questions about the product or service. If they are enthusiastic and helpful, that will be an indicator that the company is a good place to work. If they don't respond, or forward you to marketing or sales, that tells you something else abo…
For example, you could say -- "Developing Augmented Reality apps fascinates me, and Example.com seems to be a leader. Do you really get to do leading-edge work in Augmented Reality there?"