I do not think the Power 5 is harsh at all. I went from a Parasound Halo A52 which is highly regarded amp. I decided to try the Power 5 as I was very interested in ICE Module based amps but most were out of my budget. With the Power 5 being discontinued by NHT the close out prices were too good to pass up
I listened to several songs I am very familiar with using the A52 (with a Onkyo 805 as a pre-pro) right before I put the Power 5 in my system. I found the SQ to be just as good if not better with the Power 5 over the A52 with these same songs. One thing that was very apparent to me is that the Power 5 could handle higher volumes for extended periods of time over the A52. But this comparison is not a fair one IMO as the Power 5 is rated at 200 watts @ 8ohms and the A52 is 125 watts @ 8ohms.
I recently added the Rogue Audio Perseus to my system as bahorn has and it has incredible SQ. When compared to the 805 for 2 channel listening (I always used the Pure mode) the Perseus just blows away the 805 without a doubt.
So I would say try to listen to each amp if you can possibly in your own system. Both are great amps and feel you can not go wrong with either one. As psujohny mentioned earlier weight, size (depth) and low if any heat produced with the Power 5 are very positive factors for me. I have had some very big (depth) and very heavy (Sherbourn 7/2100A 125lbs.
). All were a challenge to place in my rack and not to mention a serious strain on my back.