An introduction, "I have been working on a project and I found your email by ... and I would love to hear some of your feedback as I work to continue to improve

An introduction, "I have been working on a project and I found your email by ... and I would love to hear some of your feedback as I work to continue to improve it"... Then a very short paragraph about the startup, a sentence about what it does, three sentences about the process of starting it. Then a personal plea to see if (1) they know anyone it would be useful for (2) they could spare a moment to give some feedback and (3) there is anything you can do to return the favor, but for now here's a special link to get access to the startup and I'm putting your name down so that once I start charging for features you can have a period of time for free.