Would you like to take a stab at how many DLLs, standard libraries, and toolkits NOT developed by Crestron are utilized in their programs and devices? Thousands. Crestron's S#Pro is literally a stripped-down, sandboxed version of Microsoft C#/.NET, programmed in MS Visual Studio (do not confuse this with Crestron Studio)

In regards to SIMPL? Depends on the scope. Basic residential system? Sure, who cares, throw some basic stuff together and move on. 7-figure project? Difference story.

We've shifted almost entirely to S#Pro at this point, and rarely touch SIMPL Windows anymore. A lot has changed in 15 years.