ASP.NET + MySQL大规模。推荐的？

I'm thinking of using ASP.NET and MySQL together on a large project. Does anyone have any experience in using these two on a large scale and are there any aspects I should be wary of? If there is a chance that there could be compatibility issues, then I may be prepared to purchase an MSSQL license, but I'd rather go the free route right now. In theory it's possible, but how easy is it to transfer a MySQL database to and MSSQL database in the future? ThanksI'm thinking of using ASP.NET and MySQL togethe