I got the poly ones from SCP back in 2013 and have been daily driving with them since. They are still holding up despite the PS fluid, oil and now coolant that have been getting on them lol. I did get lucky and get new ones from Ford (both sides) about the same time and still have them in the bags. Saving them for whenever these poly ones go out.
1995 Thunderbird LX 4.6- 20% tint, removed air silencer and not much else! (Mustang hubs, Cobra brakes, Vogtland springs, Mark VIII LCAs, Sport shocks and more waiting to be installed)
2013 DIB GT 301A 6-speed- 15% tint, Kooks 1 7/8 mid lengths, off-road x and cat back, Barton 2-post bracket, JPC clutch line, Koni Yellows, Maximum Motorsports C/C plates, BMR K-member, A-arms, UCA & Mount, LCAs and relo brackets, Steeda Ultralites and PHB, Shaftmasters DS, Brembo wheels- Tuned by AED