Ask HN: Will my target audience reject a .net solution?

I'm building an application whose target audience will be small-to-medium web application companies (software-as-a-service companies).

Because I am developing this solution myself, I'm planning to use something I know well, which in this case is ASP.NET (possibly ASP.NET MVC). I've tried numerous times to devote the time and energy required to learn RoR or Django, but I just don't have the time to reach a level of proficiency that I feel is necessary to support a commercial product. So, I'm thinking that I'd rather lose a little credibility with my audience and be able to sleep at night knowing that I can fix any issues that might arise. On the hand, I am worried that an ASP.NET solution might cause too many of my target audience to turn their noses up and reject the app on that basis alone. Maybe I shouldn't worry about that because I may not want those types of customers anyway?

Then again, Stack Overflow was written in ASP.NET MVC and has been well-received. But one could argue that it was largely based on the credibility and reputation of the founders and wouldn't have mattered what is was written in.

Thoughts?