That was the main question that I had -- how durable and cost effective were these wheels? According to this page (p.148) of the "The Railway Purchasing Agent

That was the main question that I had -- how durable and cost effective were these wheels? According to this page (p.148) of the "The Railway Purchasing Agent (Jan 1881)" they had a service life of 500,000 miles vs 50,000 miles for cast iron wheels resulting in an operation savings of 3.5 cents per 1,000 miles. [https://www.google.com/books/edition/Railway_Master_Mechanic/hB82AAAAIAAJ?hl=en&gbpv=1&dq=service+life+of+a+Allen+Paper+Car+Wheel&pg=PA148&printsec=frontcover https://www.google.com/books/edition/Railway_Master_Mechanic...] Given the rave reviews and obvious cost savings, it makes me wonder why|when they fell out of favor; my naive assumption would be a dramatic improvement in metallurgy? Disclaimer: statements made using an historical sample size of n=1 ;)