I had one for a while....
I think Schrade was pandering to paranoid wannabe survivalists when they made this knife. It tries to be all tools to all folks and IMO it ended up being an over busy mediocre knife. Maybe that's why they stopped making it. Don't get me wrong, Schrade makes good decent working knives overall, but I don't know what they were smoking when they came up with the Extreme design.
The spine saw was too thick and wide to saw well. The hammer butt worked OK, but the nail puller was borderline worthless. Plus, if I remember correctly, the balance of the knife was WAY too much toward the handle. Decent grippy rubber handle, though.
I don't know what steel was used, but since Schrade didn't advertise it, my guess would be 440A or an even cheaper steel like 420J2.
This is just my opinion, but I would stay away from the extreme. You'd probably be better off with a plain fixed blade from BUCK, SOG, or coldsteel for a backpacking fixed blade. If your willing to spend a little extra more, go for a F1/S1/A1 from Fallkniven (personal favorite for production fixed blades). The butt of the fallkniven handles can act as a hammer if needed. And if you still want to have a bunch of extra tools, carry a leatherman or similar tool in addition to the fixed blade.
Hope this helps.
