Mmmh, I am using LR since LR 3 and I am using it primarily, because of workflow efficiency. Another must have for me is the crop tool from LR. Perhaps I am just used to LR, so I have nothing much to complain about. My primary comparison is with Canon's DPP, which I also use sometimes. I particularly like the spot removal tool in DPP.
I am not a big fan of post-processing I have to admit. I rather concern myself with what goes into LR, trying to avoid having to fix things afterwards, but when I have to post-process shots, I prefer to do it in LR.
Nevertheless I would like to learn what is easier in other software. Perhaps somebody can shed some light on this.