I have had two Dmax utes 2009(traded when the new shape came in) and now 2012 both manuals and both from new.
No problems with either so far.
Isuzu have a good name for reliability but will not win the most Gizmo's race or be the absolute fastest or even the most modern ute(can be considered a little truck like)... but given what I read, face book groups and my own experiences etc I think they have a proven track record now with very little problems.
However nothing is perfect and no doubt an occasional glitch will occur.
don't discount a Volkswagen amarok, they are currently doing a 2018 plate clearance and a v6 is great fun to drive. the best part about the v6 is that it is made in Germany, good European build.