Is higher health spending valuable?

Yes, according to MIT economist Joe Doyle:

the additional cost of a statistical life-year-saved is on the order of $50,000 -- similar to the estimate from health improvements over time, and well below the typical value of a life-year-saved of $100,000.

This estimate comes from comparing the mortality of visitors to Florida who become ill in high-spending areas with similar visitors who become ill in lower-spending areas.