My group is considering wrapping up our Rogue Trader campaign and moving onto DH2. I've already rolled up a new CQC character, a Feudal born Adepta Sororitas. Naturally the Feudal Plate armour would seem to make a lot of sense for one of my starting acquisitions both in terms of protection and my backstory. My question is; does the rulebook clarify the interaction between basic armour and advanced weaponry anywhere? On the subject of Basic Armour it says:

"While not necessarily of lesser defensive capability, this type of armour is generally of a straightforward nature... They rarely offer adequate protection from lasgun fire or other advanced weapons, but are often inexpensive and usually enough to deal with most threats."

I cannot find the explanation for how that is supposed to work, if anyone is able to point me in the right direction I'd be much obliged.