I own Greenwire Technology Solutions (https://greenwireit.com), here in Fort Myers, FL. I'm from the area, and I've owned my company for five years now. We have 12 employees and do pretty well. That said, I've been a linux user for over 10 years now, and have a lot of professional competence with *nix based systems.
We support equipment on a range of platforms. I think it's important to be careful to not try and make a square peg fit into a round hole. There are business use cases where Linux does a great job. But I think it's important to take into consideration that those Virtual Machines, the added complexity of maintaining a cross platform environment, not having native access to specialised line of business applications, and lost productivity due to retraining; all add to the total TCO of changing to a FOSS platform. I personally know what managing these types of issues looks like, because we have environments where they are present for whatever reason. I've found in my professional experience that it's important to not try and 'convert' users. But rather to act as a good trusted adviser and find a solution that is minimally disruptive to their business.
