We're working on an ASP.NET web application with C# code behind. The database is MySQL 5.1 using InnoDB. The data access layer uses ADO.NET to call stored procedures and then builds various data structures out of the result sets (no object mapping). This works fine, but it is a little verbose.
Not surprisingly, we made some mistakes when designing the first version of our data model, but the experience has made us smarter and we decided to refactor the data model. We don't have to change our data access layer, but we are considering our options for that as well.
It's been difficult for us to ignore the popularity of ORM tools these days; we feel like we are way behind or something for not being familiar with them. Not only that, but we have already designed an object model that nicely describes our data model. The main ORM tools we would consider are NHibernate, ADO.NET Entity Framework, and LINQ to SQL. We would prefer LINQ to SQL because we have read (on S.O.) that it is more light weight than full ORM tools.
We think one drawback to using an ORM tool is the learning curve, but we can already see how using LINQ could reduce the amount of code we will have to write, which could save us time in the long run. However, we are using MySQL, not SQL Server.
So my question is, would DBLinq work well enough for a production system? Or, is LINQ to SQL a compeling enough reason for us to make the move to SQL Server 2008? Incedentally, I'd prefer to use SQL Server over MySQL, but cost is the obvious drawback. After 3 years on BizSpark, we'd be on the hook for $6K. Or, should we consider other ORM tools instead? Or, should we just ignore the hype and not use an ORM tool, but maybe take advantage of LINQ to DataSet?
I searched S.O. for info on DBLinq, but only found 17 questions with the DBLinq tag, so it doesn't appear to be popular.