I do all my startups and projects in .NET as well as my consulting, but it's hard to find startup clients as not a lot seem to use .NET. I think it's amazing and rapid and the best, but people just build with either whatever they are good at or whatever is really hot at the moment. I've been learning .NET for a long time, so it's what I use.<p>I was going to make a blog ".NET for startups", but after the first post I realized what was the point because of the above points. BizSpark was awesome but they just killed it which really sucks.
I don't know if you'd call my company a startup as such, but we use the MS stack. However, the reason for that is because I knew it very well before starting the company. If I were a Java expert, I'd have used that, and so on.<p>Given that .NET Core is now pretty good, you don't have to worry about buying Windows licenses for your servers, and you can use VS Community so long as your company is small enough, so your startup costs aren't too bad.<p>In conclusion, it's been an excellent experience and I would recommend it, if you happen to know the MS stack well yourself.