I did it on my new TT in 2004 and have kept it current ever since. Haven't had to use it, but it's nice to know it's there. The way it was explained to me was, the extended service plan takes effect after the MFG warranty expires. Mine runs about $500/yr with the Gold Coverage. Read the policy carefully so you know what to expect.
2014 Wildwood 27RKSS 2004 Nissan Titan Pilot Steve
Co-Pilot Marlene Furry Four Leg children: Fancy Lab/Chow, LB Little Bit, Maltese, Rocky, Border Terrier