Well, let me clue everyone (especially FD) to something. I can have a good ship with prismatic shields and if I go up against a player who is ranked dangerous, deadly or (shudders) Elite without prismatic shields, I am going to be unbuttered toast!!! And that's if he's nice. If he isn't nice, I'm going to be a blackened, very crispy critter. These shields give you an edge. They won't save you from a superior adversary whose only thought is to add you as a notch on their gunbutt.
I thought the Imperial Courier already had prismatic shields. The only way I can take down the shields of one of those beasts quickly is with a class 3 beam laser or two. I had a diamondback explorer with 1 class 2 beam and 2 multicannon 2's. Took forever to take down an imp courier's shield. I put a 2nd so I had 2 class 2 beams and 1 multicannon 2 and it still took an inordinate amount of time to break it's shield, although it was quicker with 2 than just 1. And this was on an NPC courier. Against a human, I wouldn't have survived it; or if I did, I would have tucked tail and ran, praying my luck didn't go even further south.
I've flown the Courier. That is a good ship. Fitted with some shield boosters and it is one dangerous critter. Only down side is only 3 weapons and all class 2.