My JRT loves this!
I usually put it by the window so she could look outside to see what's going on, and at night I move it by the bedside so she can climb up to sleep with me.
Each step is slightly slanted towards the bottom so it's easy for you pet to climb, but not slanted too much to loose balance.
My dog likes to sit on the top step while she browses out the window. 
Solid construction but easy to assemble, no tools required.