I completed the process in a few hours using the directions provided by Instructure. It wasn't very difficult, but I did have to fill in some gaps here and there with trial and error or guesswork. You don't need any hardware. The only additional software is the two SIF components from PowerSource and you will need database credentials for the SIF connection.
I didn't collect any performance data, but I can't imagine that there are negative effects. It's likely that SIF is much more efficient than the previous method. Given a more efficient method of data-sharing and a similar quantity of data, the performance should increase.
We needed to select remote server and put in the ip address of the database server. When we were configuring database on the PowerSchool Sif Agent we needed to replace the localhost designation with the inside ip address of the database server. You need to use the standalone agent to get to the configuration settings but the powerschool sif service must first be stopped. After the settings are in place you must shutdown the standalone sif agent and restart the service.