I have a '13 ST-S and love the V twin engine. If you can get the '13 RT for $9000 off MSRP and make sure they do the heat recall, then go for it. I don't think you will be disappointed.
2020 F3 Ltd
Spyderpops Bumpskid Spyderpops Brake/Run/Turn Signal LED's
Lamonster Garage LED Fog Lights and Headlights 2013 ST-S retired 1/9/16 at 25,061 miles
2015 F3S sold at 77,565 miles.