I am running an older SCS PTC-11Pro. It does control the radio. Like most of Pactor modem users once you use your computer to control the radio you will be very pleased. For us it was well worth the extra charge. Would we buy another one again? Yes without hesitation. Many times we switch to many different frequencies before connecting. By using the computer its just a click versus turning the knob, etc. Much Faster and easier
Also some of the older models like ours do not have a USB connector. So we had to purchase a converter to go from the old pin style connector to a USB. The newer modems are now setup with the USB to USB fittings. Makes it much easier and one less piece of gear you have to buy, install and fix.
So my final vote is to spend the extra money and go with the SCS modem that will enable you to drive the radio from the computer.