No argument here, its just my materials geek coming out.
You are totally right, the coefficient of thermal expansion is really good for Ti.
I'm not a big fan though, for the aforementioned ME issues and what the other gentlemen referred to, the fatigue cracking propensity.
Bottom line, I am really biased to Ferrous metals. Titanium scares me. I have been part of weld failure investigations, and when it comes to Ti (yes probably few welds on a receiver) the fatigue mode for failure is really unforgiving. You can have subtle unseen cracks develop and fail without visible warning.
Job knowledge: CTOD testing (May 2005)
HOWEVER, if Remington is putting it out, i'm sure they have it dialed in.