Your top priority should be to be available for as many people as possible. If you can get more than 1000 people on your server at once then you need to take ad

Your top priority should be to be available for as many people as possible. If you can get more than 1000 people on your server at once then you need to take advantage of that momentum to build a buzz about your product. Putting artificial roadblocks in the way is fine, but at least create the CORRECT roadblock. Instead of a "Server unavailable" when the user attempts to try things out, maybe have a separate server running a static version of your product which can be served quickly from cache that a user can play around with while they wait for availability. Or find a way to improve the caching on the website so support a higher number of individuals. You could offer them access to the live application if they leave their email address with you. And then you could stagger the invitations for live accounts over a longer period of time without losing any potential leads. Do you collect personal information upfront? I personally think you should let the customer play with as much of the application as possible without forcing them to commit personal information. The fewer barriers there are, the more time the user will have to explore your value proposition. If you have limited server resources, it might be worth it to invest a few bucks for a couple of days on a beefier server just for your launch. You probably won't need it longer than that and you can probably afford an AWS instance for a few days.