My sister has my "hand me down" iPad 1 and she still uses it every day. I got it in August 2010 and it's still going strong. Granted, she's not a power user, as I am, but I've not heard a word of complaint from her concerning the operation of it. And yes, it only runs iOS 5.1.1, but it runs it well. Physically, the thing is in great shape. It starts right up and does what she wants.
There are other iPads owned by my immediate family: Mom's iPad 2 was bought in May 2011, my brother has an iPad 3 bought in March 2012 and another sister has a Mini bought in November 2012. They all run the latest iOS (7.0.4) very well. No one says they have any issue and believe me, these three iPads are used daily, a lot!!
I'm very pleased with the quality of the products. As is my family.
Marilyn