Big Prints Cost BIg Money
I wouldn't pay for the pasted one. If this image is that good and really important to you, you won't regret paying $150. It's not that much money in the long run. And I bet it won't take long for you to start questioning the two-piece version.
What's your digital experience like? Can you set up a 60 inch file yourself? Do you know about ICC profiles? If you can set up a file right, I bet you can find a cheaper way to get it printed. Calypso Imaging charges $9 a square foot for LightJet prints if you can set them to their specifications.