Dearborn vs. Alpha/Belden wire prices/quality?

Hi:

I can't believe the price difference for 18 ga. 19/32 strand MIL type B wire at Allied:

293-1360 Dearborn 171819 $17.63

Newark has wide price differences as well. There's gotta be a catch. I have some Dearborn TFE wire which I've never had trouble with, though I guess I do think it's a little lame to have a splice in the middle of a spool. But the stuff does conduct electricity, and the insulation doesn't. What more should a wire do? Is there anything wrong with Dearborn?

BTW what do people think of irradiated PVC wire?

Also, all these darn agency and MIL ratings are annoying. I only care about volts, temperature, sometimes insulation thickness is relevant, and insulation material.