URL Design for SSL-Secured SaaS Application

Question

I am developing an application using the ASP.NET MVC platform, which will be exposed as a service over the web (the SaaS model). I am trying to determine the best way to partit

Answer 1

I would go with A. This solution is not very expensive, it scales well and it does not limit you to go with custom domains, if you decide this later on.

Wildcard certificates used to be quite expensive, but today you could get them around 200 USD annually at GoDaddy or RapidSSL, which I think is pretty cheap. These certificates works in (almost) any browser, but they doesn't come with the validation, VeriSign provides. I don't know whether you need this.

If you go with option B, you have to purchase a certificate per user, but with a wildcard certificate, the certificate will be paid after a few sign-ups and the rest will be pure revenue.

Aside from this the solution is really simple to implement, which also is a strength.