MOLLE is just a way of attaching one thing to another, saying 'oh, it just looks like MOLLE gear' is a bit like saying, 'oh, it just looks like quick release clip gear to me...'.
nonsensical.
personally i wouldn't use VIRTUS, the quality control has been a bit hit and miss (like the early stages of most things), and the 90l bergen doesn't have a hip/waist belt. think about that when you've stuffed it with a weeks worth of kitchen sink...
if you've got the shekels to buy a VIRTUS bergen, i'd reccommend trawlling fleabay for something in the Berghaus Cyclops range - the Vulcan is the popular favourite, but i prefer the Cyclops Roc and the (old style) Cyclops Crusader. both last forever, and both come in at well under 2kg - the Vulcan is well over 3kg...
the PLCE bergen has several good points - it is simply indestructable, its cheap as chips, there are a number of companies that will modify it for in almost any way you want, but its relatively heavy (about 3kg iirc) and some find it uncomfortable.
the old Cyclops Crusader was the template that the MOD used to produce the PLCE bergen - indeed Berghaus actually did the initial production runs, but the MOD subsequently went elsewhere for large scale production, almost certainly on cost grounds.