One more feedback. In my current playthrough I began to start avoiding picking up machines because they might turn into scrap, and in the early Marathon AngelBobs game resources are very tight. I like the idea that planning layout ahead is beneficial, but with the cost of belts in these games it's not always practical.

Anyway, the current penalty of needing to surprise create a whole new machine feels a bit harsh in this case. Though I understand the need to remove the "mine to repair" exploit. Also the tech to recover machines is quite a way off.

One thought I have is to create a middle ground for mid-age machines (say, between 20-60% age) that mining creates a machine in need of refurbishment (at say, machine + 50% cost), and an associated tech that is earlier in the tech tree to enable such things. Since you already are creating scrap machines, maybe this is not too much work.

Another thing along this line that would be useful is to have some age data in the GUI, so I can see how far along a machine is in it's lifecycle and the risk of interacting with it.

Thanks again as always :)