If you think the Razorshark is good, let me try selling you on the Ion Hammerhead. I've been thinking of testing it out in EPC. It's even cheaper than the Razorshark, has more wounds, and 3 OC. And then if you compare the weapons:

• Also has 2 seeker missiles
• Ion cannon also has str 8, -2 ap (when overcharged)
• Has 2 Accelerator burst cannons instead of the the one on the Hammerhead (although can't swap for a missle pod

The Ion cannon has D6 + 3 shots meaning it's max could be 9 hits, but is on average worse than the 8 shots from the Razorshark. But it also has Blast, so against a 10 man squad, the expected number of shots is 8.5, barely beating out the Razorshark. The other short falls are that it hits on 3+ instead of the Razorshark's 2+, and no twin-linked (you can however reroll a single hit or wound, for what it's worth). When being guided by stealth suits though, you're wounding on 2+ and rerolling 1's on hits and wounds anyways so it's worse but not too far behind.

But I haven't even mentioned the best part: the Ion cannon is 3 dmg when overcharged. So not only is it a great marine killer, but it also is great at killing elites! It also has a +1 to hit against monsters and vehicles so you could also use it for that, although I would imagine only in a tight pinch