Hello. Can you please tell us the monitor model numbers?
All depends on your needs. Usually a refurbished or open-box product carries a limited warranty. But this may still be a great deal. If it is manufacturer refurbished, you usually do not have to worry about quality, and only the warranty. On the long run, a new product with a full warranty is more safe, but there's no absolutes.
I'd say in the end, it depends on what you want to do with this monitor. If you will play games that support ultra-wide resolutions, then the first monitor could be a good deal. But you will need a faster PC to drive it fully.
A 1440p monitor is good enough for most people.