In my system, the Mullards took away a slight shrillness I was getting in the upper mids. As for the difference in sound with the McIntosh VS the Rogue, that's a bit tougher. The all around sound is much more to my liking which is a smooth but not extremely detailed sound. I replaced the preamp and power amp at the same time so which one contributes more to the sound I am getting I can't be that sure. I will say I like the sound of the system with the McIntosh factory tubes and have no desire to experiment, although the guys on the Mac forum tell me the Gold Lion tubes are more of everything. I'm sorry I can't be more specific than this.