The Professional Edition is for those users who want all the features that SimTools has to offer. The Professional Edition is also for the builder/wholesaler that wants to provide a copy of SimTools in conjunction with a simulator or simulator kit they sell.
The Professional Edition is not intended to be loaded on a simulator that cost money to ride. The Entertainment Edition is available for that.
SimTools only comes with the game plugin Live for Speed. Other game plugins are available at Xsimulator.net.