Designing a Heavyweight

[overkill]

Wow that is a good find, so you'd just need 2 of them and then 2 relays of some sort to complete an H-bridge, some sort of microcontroller and you have an esc? Though for that price it's probabably cheaper to use 4 of them using 2 just as on/off relays.

No, these parts will not carry anywhere near the current stated - its a theoretical maximum in perfect lab conditions. Using the numbers in the spec sheet, one of these FETs can carry 25A without a heatsink. With a reasonably sized heatsink, six of these will carry 150A comfortably but the spec sheet doesn't state the maximum current that the case pins will handle. In many small to medium FETs the pins will melt between 50 and 75A so with a small surface mount pack like this, its not going to be higher than that. You can get much better cost per amp with the IRFP4004 FET at only £22.10 for ten.

Its also very hard to drive a bank of FETs - it takes an experienced electrical engineer and plenty of trial & error to make a reliable ESC.