I drive my SRT8 every day............I find it to be comfortable and the ride is smooth....can't see the RT being that much better in that department, but havn't driven an RT so I really don't know.
My mileage is descent and I still have all the power I could ever need on the road.
In addition I have had two incidents where I had to make an abrupt lane change due to a "distracted driver" making an "unannounced" and last minute lane change directly in front of me. The SRT handled like it was on rails...saving the day.
Bottomline is, I am glad I own an SRT....and have been very happy with it for almost two years now.
If cost is a factor....go with the RT, but if you want the King of the Hill....go SRT
(Just my two costs....)