The Track key for the Boss cost $302.00. I have seen it as low as $260.00. Then you have to pay shop labor to install, usually an hour or two labor.
No peak HP or TQ gains, been proven many times. For the Boss, Track key did require & use a dual path ECM, so maybe the late 14's & future Mustangs will have as standard equipment.
The 'lopey idle' is just a gimmick that makes it sound like you have an old school cammed engine.
Check into the warranty before installing, especially if you opted for any extended powertrain warranty.
2012 Race Red Boss 302 # 1055
Torch Red 2006 GT
20 Yrs of Mini-vans
Grabber Blue 1970 Boss 302
Lime Green 1969 Notchback Coupe
Maroon 1967 Vert