Wheel base defect coupled with incorrect left side castor setting, both courtesy of Mazda Japan at the time of manufacture. The manufacturer has been unable and unwilling to accept that the fault even exists, yet alone do something about fixing it. The defect causes high speed instability, wandering and strong reaction to changes in road camber. This makes it exhausting to drive long distances on lower quality roads.
Something like 30 other faults:
Rear suspension link striking on sway bar - took dealers 20 months to fix.
Scratched dash board at time of delivery.
"Creaking" front door trims when heat soaked.
Loud air conditioner clutch engagement.
Gear train rattle when hot.
Dealer caused other faults while fixing problems e. g screw driver marks on dash, forgot to put door trim pieces back.
Door seals coming off.
Three out of round/buckled wheels at time of delivery - cause still unknown.
Headlights aimed too high.
Idle problems due to carbon build up in throttle body assembly. Not fixed due to dealers taking short cuts and not cleaning out assembly at service time as they are supposed to.
Exhaust banging loudly on tow bar assembly.
Chrome tip on exhaust has been replaced twice since new.
Paint spray on rear left quarter panel when delivered.
Polish damage to left door handles and mirror when delivered.
Full of faults.
Hopeless dealer and manufacturer support. People who complain are treated like lepers.
Owner needed to seek independent engineers report re wheel base and castor problems, however even when verified 100%, Mazda refused to accept report or existence of faults.
Comfortable, very economical, reasonably quiet, good value for money.