I have done some work programming in C# at Triton Technology Ltd. and then Lacerta Technology Ltd..
When we developed the software for the identiPol QA we used Vb.Net which was the logical choice as I already had extensive experience using VB6 and VBA and some code that could be adapted. Our hardware/firmware designer had more experience with C than with Basic based languages though so he chose to develop some of the in-house testing and configuration software using C#, and later I helped continue to develop and maintain some of these systems as well as adapt some of the code for use in our main software products.