boowho, not sure about State Farms, but FYI we have AAA with RV coverage, and they said they'd cover tire issues except in some cases based on the availability of a vender to change MH tires. Sounded too hit an miss for us so I got specific tire service coverage. As to carrying a spare hunk of rubber, I probably would if I was going to Alaska, or an extended X-Country trip.
2012 Winnebago "Journey To Insanity" 40U
2008 Dakota Sport 4x4
2004 Subaru Baja - DW's
2006 Honda Shadow Aero - TOAD for now.