They're not sacrificing anything for the Plasma proc. They're sacrificing a mod for the Disruptor proc. They are Plasma weapons with a Disruptor proc... they're not Disruptor weapons with a Plasma proc.

I don't have any Plasma Array Mk XII's, so I'll just give the min stats from ESD looking at the Exchange, eh?

Plasma Beam Array Mk XII [Acc]x2 [CrtH]

227.9 Plasma Damage (182.3 DPS)

2.5% Plasma DoT (26.8) for 15s

+20% Accuracy

+2% CrtH

Romulan Plasma Beam Array Mk XII [Acc]x2

225.4 Plasma Damage (180.3 DPS)

2.5% Plasma DoT (26.5) for 15s

2.5% -10.5 Damage Resistance

+20% Accuracy

So it's not just the mod (+2% CrtH in this example), but you'll also notice slightly less damage for both the beam and the DoT...while adding the potential Disruptor proc.

Of course, the Rom Beams come in all sorts of flavors: Accx2, CrtHx2, CrtDx2, Dmgx2, and the various mixes of Acc/CrtH/CrtD/Dmg...

It comes down to how much is that Disruptor proc worth it to you - remember, that's -resistance is hull...not shield damage.

That first Array I listed, the cheapest one is 1.8m EC. The Rom one is 28540 Dil. Let's do some fun conversion stuff, eh?

A Lockbox Key's 1.4m EC. A Lockbox Key's 125 Zen. 1 Zen is currently 90 Dil. So a Lockbox Key is 11250 Dil. 1.4m EC ~= 11250 Dil.

28540 Dil would therefore ~= 3.59m EC. Is the Disruptor proc (-mod, -dmg) worth around double the price of the Array?

How about looking at a couple of other weapons out there to see how they work out, eh?

Phased Polaron Beam Array Mk XII [Acc]x2 - 2.4-2.8m EC

Polaron Beam Array Mk XII [Acc]x2 [CrtH] - 1.25-1.44m EC

Polarized Disruptor Beam Array Mk XII [Acc]x2 - 3.4-3.6m EC

Disruptor Beam Array Mk XII [Acc]x2 [CrtH] - 3-3.45m EC (only two there)

Phased Tetryon Beam Array Mk XII [Acc]x2 - 10-15m EC

Tetryon Beam Array Mk XII [Acc]x2 [CrtH] - 1.5-2m EC

Then there's also the Spiral Wave Disruptors to consider, eh? 45380 Dil for [Acc]x2 [Dmg]x2 with Phaser/Disruptor procs...and you need to have a Galor in the first place to buy them.

Obviously you can't convert the EC to Dil to buy Zen, etc, etc, etc - but you can go the other way, so it does give you a rough idea on comparative pricing in that sense...like the SWDs being around 5.7m EC each (the amount of EC you might be giving up if you did not convert your Dil to EC via Keys).

Depending on how feels their luck goes with procs, they could probably split Rom and non-Rom, eh? Etc, etc, etc.

On my guy running them, mind you - I took four. Why four and not six? Because it's four of them, the Experimental Beam Array, and the Cutting Beam... mixed in with the Hyper-Plasma and Omega Torps... I think the addition of the Disruptor proc is worth the additional cost.

Whether Plasma is worth it in the first place, is another discussion - but if you're already going that route...

Willard the Rat, Reman, F.T'varo - Rave, J.Trill, Kar'Fi - Mysk, Gorn, Varanus

Maal, Klingon, Mogh - Vegar, Orion, Marauder

Nivuh, Ferasan, B'rel - Venit, Lethaen, M.Qin - Kopor, Nausicaan, Guramba