ISUZU DMAX is more muscular and sturdy machine. if you are planning to keep the truck for few years. It is more comfortable and got more power equally on & off pavement.
Toyota 4x4s are only cosmetics and attractive resale. Maintenance of Toyota 4x4 Trucks are more expensive, reason is Govt Security Vehicle Fleet., not commercial truck.
2nd most important point is ' It is most sought after 4x4 truck by criminals for gun point snatching ' over the long routes.