How does the JSF stack up against our current inventory, excluding the Raptor?
JSF has greater stealth properties than our current fighters, but it has a smaller payload. I'm not sure about range.
The JSF is not a single aircraft, but three different aircraft with lots of similar components, but lots more stealth than the planes they replace.
The Air Force version is supposed to provide similar capabilities to both the current F-15 and F-16, including some air to air but lots of air to mud. It's not meant to be overwhelming air superiority, like the F22 is, but it's supposed to hold its own against anything out there.
The Navy version is altered for carrier landings, etc., and is supposed to be on a par with the F18 family.
The Marine variant is a VSTOL to replace the aging Harrier. It is supposed to have the most dramaticly increased flight envelope and weapons capabilities when compared to the AV8 it replaces in this variant.
All of the variants are supposed to be an order of magnitude less expensive to operate over their lifetime than the planes they replace.
Then the Raptor (or Lightening II, as some would have preferred) is supposed to just outfly anything ever dreamed of, short of science fiction.