Fact check in aisle zero. Microsoft's CLR profiler is freely downloadable, no linkage to IDE versions. Additionally, there are two tiers of VS above Express, Professional and Team Suite (VSTS). VSTS comes in different editions, it's a bit convoluted but mostly irrelevant because most folks doing this for a living have an MSDN subscription (or they should, as it pays for itself pretty quickly just for dev/test licences). Collectively, these tools are frequently used to build mission-critical software for large corporations, which is probably the largest difference between MSFT's developer stack and APPL's.