I run quite a bit and I loved my GT-2160s, but when the model was discontinued I had to find a new shoe.  The reviews for the 2170 weren't great but I tried them on in a specialty running store to decide for myself.  I wasn't a fan so I decided to give the GT-2000 a try.  It took a few miles to get used to them but I'm a believer now.  The heal cushion doesn't feel as soft as the 2160 but everything else works well for me.  I just bought another pair last week.  The GT-2160 is still my favorite shoe but GT-2000 comes in second.