we have 23 delivery trucks all isuzu. very reliable, dati mixed ng isuzu and mitsubishi's canter and l300 but mas reliable pa din isuzu. yung iba sa mga truck namin almost 15 years na and still in good condition. araw araw pa sagad karga non.
My uneducated opinion is that if you're gonna use it 24x7, go with the one that is more repairable. Kahit anong ingat e malalaspag din yan sa driver/road conditions/etc. Might as well get the one with the most spare parts.