I wouldn't consider S90V a "current" knife steel since noone is mass producing knives with it yet. IMHO, S30V and the Falkniven 420 Laminated VG10 are the best things out there for survival purposes. If you're on a budget 154CM/ATS-34 is a real good compromise. If you need to go even cheaper, some mfrs like Benchmade actually do a respectable job with 440C but I would be careful about who you get your 440C from or you may find holds a worthless edge, dulls, folds, etc. There are lots of great carbon steels available also but I wouldn't recommend a non stainless steel for survival, but that's just me (IIRC Doug says something similar in his article on sharps). I believe in keeping survival gear as low maintenance as possible. Uncoated D2 will rust up pretty quickly too. Even Moras come in SS and Laminated versions.