I picked up my 28DSBH yesterday, and with the advice from this forum, went ahead and bought the extended x chocks and put them on when I got home. They worked great.
2014 Ford F-250 Lariat Crew Cab 4X4, 6.2L gasser, 3.73
2013 Jayco White Hawk 28DSBH
2012 Ford F-150 Lariat Supercrew 4X4, 3.5L Ecoboost, 3.73 (traded)
2005 Jayco 1207 (second PUP)
1976 Coleman Brandywine (first PUP)