Like several others on here, I bought a D5100 & used it all of last summer. In April of this year, I bought a D7000. I had no problem finding a new one.
The articulating screen on the D5100 might be handy for some, but all I could see was my reflection. Really difficult to see what I was trying to shoot. In some cases, I totally missed the desired subject. I shot video & stills while still at the same venues. I found that it was the easiest to shoot Aperture mode only. I set the Fn to control ISO. The big problem I had with the D5100 had to do with the inconvenient placing (due to placement of articulating screen) or lack of controls. Only one command wheel.
Hardly ever use the D5100 anymore. If I do, it will probably be to use in multiple camera situations. At track meets, I sometimes need different lens. It is often inconvenient to change lens in the middle of an event.