I've used SimpleScripts before on 2 different servers. Both are on 100Mbps connections, yet the performance was real slow and sluggish. I know its not on my server's end since it was tested on 2 different servers on US and Germany.
Also, its a pain uninstalling it. You have to rebuild sprites yourself, and on some occassions, you need to rebuild cPanel's PHP config (this is rare though).
Good luck with it
