ZyDoc is a great company to work for. I began working for them in 2008 as a remote employee. This was my first experience as a remote worker and it took a bit to get used to however, ZyDoc has been great with any support I needed to do my job. I can't recommend them highly enough.
Cons
The only con to being a remote worker for any company, not just ZyDoc, is it is hard not being nearby to participate in company events.