I’ve had two, a 2010 and a 2012, can’t say I could feel any difference.
My only comparison was with a Giant Anthem 29er which I found far to head down and lively and was glad I went with the RIP but it is very much personal preference and I like riding down more than up.
For the last two years it’s been my only bike, I did have others but every time I went to the garage I came out with the Niner so I got shot of the them.
You feel like you’re part of a family, especially when Chris Sugai (Niner boss) comments on your bike on facebook and Steve Domahidy (the other boss and CVA suspension designer, now left unfortunately) personally answers your technical queries by email. Customer service is legendary and it’s deserved.