Planet X Pro Carbon Evo - Thru Axles

When I attempted to remove the wheels of my brand new Planet X Pro Carbon Evo (to fit new Hunt wheels) I managed to strip the hexagonal profile of the thru axles, and I had to go to my local bike repair shop to get the wheels removed.  Customer support from Planet X was very poor and slow but eventually they sent replacement axles.  However, even on the replacement axles the depth of the hexaganol thread is only about 2-3mm - so this seems like a design flaw and I'm reluctant to fit them in case I strip the head again.  I've looked for replacement axles (preferrably with handles) but I can't find the correct size.  And I don't understand the difference between the adverstised size (front 100, rear 142) and that printed on the parts (front 120mm, rear 169mm).  Also, I don't know what torque to apply - I'm paranoid about the thread unwinding and the wheel detaching!  Can anyone help, primarily with sourcing replacement thru axles.

Front: 120mm (100mm) x M12*P1.5*L14

Rear: 169mm (142mm) x M12*P1.5*L14


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