I apologize since I don't know much about NY... Your question about Kissimmee vs. other Central Florida communities is like asking about the Bronx vs. Manhattan or Brooklyn vs. Staten Island. The areas are distinctly different, each offering their different pros and cons. Kissimmee (Osceola County) has some development and prosperity, but most of the area is blighted with foreclosures, half-completed developments and poorly-rated schools and impoverished strip mall-type locations.
Florida can be deceptive to someone looking at properties on a map. Florida is a fairly large state with everything spread far apart, and with very little functional mass transit. There are some very rural areas in Florida, some even without internet access. There is no subway (often no bus system) to take you to/from frequent destinations; you have to make mind-numbing drives everytime you want to go somewhere. If feasible, I would recommend investing your time/money to fly down here and rent a car. Look at the distances between the different areas you're considering and your job location. Look at the surrounding area of your home and determine if you like what the area offers. Driving an hour or more to get to any kind of entertainment or "civilization" may not suit your lifestyle.
In short, I've lived in Central Florida for a number of years- from the backwoods of little known places to the bustling urbanized areas near downtown Orlando. I've found that Clermont, Lake Mary/Heathrow and Maitland offer the most comfort and best location for me regarding my family aspirations (having children in the future), career (more employeers should I decide to make a change), and entertainment (some entertainment offerings, but a short drive to Orlando attractions/nightlife).
Good Luck in your endeavors.
