This looks like an interesting engine development, but just what is the "critical mission need"? What is the specific application for it?

Is the mission need the methane/oxygen combination that was going to power the Orion service module, just overcome by events?

Didn't Northrop Grumman just acquire TRW? This is that heritage, TR408... It could well have a pintle injector in there. :)

Been there, done that. Our friends at Orion Propulsion, under contract to HMX for t/Space's CE&R (NASA), did this very same job in 2005. 100 lbs F vac thrust. Pictures are on their website: orionpropulsion

Methane is a lot easier to keep in a tank than liquid hydrogen. Lower rate of venting to cool it, or much smaller cryo-coolers, take your pick.

On year long interplanetary missions, if you don't want to bleed off half your fuel to keep the other half contained, or run energy expensive active refrigerators, methane is a good way to go.

Besides, it's much denser - less tank per propellant mass even if the propellant is less efficient.

Oh, I don't think you'll find much disagreement on the benefits of methane engines here... it's just a question of what drove the funding for this in light of NASA's current fuel choices.