That's a tough question to answer, currently since I have worked so much with so many other softwares one of the benefits I am offering is the diversity to keep things as they are if the office wants and I work within their system. So far this has been a real benefit in my marketing. Obviously, if you have not had the experience with other softwares it can be a challenge and maybe not so efficient to do. In that case all you can do is reassure the provider that a conversion (gradual as you are doing it) is in their best interest as long as it really is.
The advantage however is that if they have called you, that means there are other issues they are having and you can focus on those rather than "software" issues. Hope that makes sense.
I signed two clients and another one next week, and with all three I will be working on their software. I have another one on the line who is a new provider on his own so software isn't an issue. If a provider is using one of a couple of softwares I absolutely detest I will go over all the pro's of a conversion to use mine. my two least favorite softwares are Medisoft and Therapists Helper, in those instances I will go over all the downfalls to those softwares.