It was about time i revisited this project.
The boost converter i had initially was a beefy "600W" part that seemed like a good idea back then but only runs good at around 17V+. No chance at 12V to get full output power.
So i got a new "250W" one that claims to run down to 9V, bolted to an old pentium 3 heatsink and tested it at 12V. It draws about 14A at 12V which is way over the claimed 10A it is capable of but with some added output capacitance and overkill cooling i see no issues. Should be completely fine at higher voltages and even at 12V it achieves maximum output power :)