Heh, I can vouch as far as Alistair's Squid policy. Thank goodness he painted the ship black; the stains would be awful.
As far as heatsink, often its a matter of ship and engi help as to if I take it. If I can trust the engineer with me then I don't take it. If they are still learning the ropes, or if its a big ship, or if I know they have fire on the other team I take it. More then once heatsink has saved my skin. When I am on the heavy flak, it reloads fast enough to put out fire stacks and helps me out if the enemy ship is closer then I like with the reduced arm time. And when the enemy is feeling cheeky and flies with a bunch of flame throwers, its nice to ensure you have something to shoot if the engi has a bit too much on their plates to chem spray.
All in all, I'd say its situational, but in my opinion, it's pretty handy.