An xl 280 engine if it were possible to be damaged down to 0%, would cost a mere 57,200 while having a sale value of 0. The same xl engine at 25% has a repair cost of 42,900 and a sale value of 571,666, when repaired it's sale value goes up to 2,286,667. This has a derived repair cost of ~0.93% of original cost to repair, while armor has a full priced 25% of original cost to repair. This is pretty much derived from the given values for minimum health for each item.
At 10 tons of armor(100,160) stripped off from a lengthy match you can expect a repair cost of around 25040. If you were to plug in the % of the reactor costs it would cost a mere 940 cbills, thus becoming very profitable and comparable to structure repair costs.
I'd recommend however a 10% repair cost of armor, making it around 1000 cbills per ton of armor, while this would also make ferro more viable due to it's current repair costs are kind of out there. A fully armored atlas would pay ~19-20k on a full stripping, which happens quite often from what I've seen. Compared to 47,576(25% of his armor original costs) which makes repairing a xl fusion reactor cheaper than armor. While if I use the same % as my own reactors costs it costs 45964 to repair a 300XL, it still costs less to repair the repair from 25%.
Even if it is justified by buying new armor, it wouldn't make much sense to have it cheaper to repair a fusion reactor than it does to repair armor. It is understandable that it should cost more money to repair your tier 2 tech more than your standard stuff, but a tier 2 tech item should not have lower repair costs than a tier 1 tech item.
Edited by Deadoon, 27 November 2012 - 10:16 PM.