I would stay on I10 to exit 85 at Defuniak Springs and go north on US331 to Florala, AL. Turn left through town and continue west on AL 55 and AL 106 to join I65 at mm 114. Then north on I65 and on to Memphis as others have said.
All good road, light traffic normally and Andalusia, AL almost always has the cheapest gas/diesel prices around.
Ed
KM4STL
2006 GMC 2500HD CCSB 4x4 Duramax/Allison, Titan 52 gallon fuel tank, Prodigy Controller, B&W Companion Hitch, Progressive Industries EMS-PT50C, TST Systems 507 TPMS
2010 Jayco Designer 35RLTS,Cummins/Onan RV QG 5500 EVAP
Fulltime since 2010