Dedicated line w/ upgraded parts or power cond?

Yes you should.This will make it easier to judge differences in power cords.

Rockdanny - replacing the iec inlets on hi-fi components is not always as easy as it sounds - so before ordering, open up each component to ensure it is something you are prepared to attempt or pay a technician to do.

Also, better quality components may well have perfectly good iec inlets. So you may be changing something that may make little or no perceivable improvement.

Having said that I have replaced iec inlets and the improvement was quite noticeable, but that was in one of my DIY projects where I was certain the one being replaced was pretty crappy.

If you are replacing them with Furutech or Oyaide quality iec's, then at least you are assured of their quality and as Lacee points out - you have no doubts that improvements are due to power cords.

Also, ensure that making these changes does not void any existing warranties or UL certifications

Replacing a power cable - simple - plug it in
Replacing a part in a component - a little more to consider

This type of tweak boils down to how much responsibility YOU are prepared to accept :-)

Willie- thanks for your clarification. I will know more once I dig into the E=T set up. It is easy enough to have the cables reworked by the manufacturer if needed. I also don't know how this corresponds with US electrical 'code' requirements, which is something I want to comply with for safety/fire hazard purposes. I have usually worked with a licensed electrician whenever I do anything re wall power- unfortunately, most garden variety electricians know little about sound.
I'm probably going to use someone versed in studio set-ups and commercial wiring once I get to the next room- since I'm relocating from NY to Texas. My goal has been to find a residential property with a separate outbuilding, or the space to build one, dedicated solely to 2 channel listening. Such space is now at a premium in downtown Austin, but we haven't committed to buying a property here yet.
I gather you are in UK or EU?

I replaced one set of receptacles in the 15 amp Furman with a spare Shunyata RZ1(?).
It was a bit of a squeeze wire wise,but the recptacle the Shunyata replaced was really quite shabby.

I use this Furman in my HT set up and I have the 5 channel ower amp plugged into the Shunyata receptacle along with the processor.

If I was seroious with the HT system I would replace all the receptacles in the Furman.
The 20 amp Furman version had more robust receptacles,but I still replaced one of those with an FIM at one time.

If there's no warranty,replacing the recptacles in power conditioner and the IEC with better ones,is worthwhile and not hard to do,just make sure you make a diagram or take a picture of how everything is wired up.

I'm not a klutz but I'm no EE either,if you're careful there's a lot of little things you can do to improve gear that is of good design but cheap parts were used to cut costs.

Call me a Furutech fan boy, but all the connectors I've sourced from them,as expensive as they are, haven't failed to impress me with their build, and reliability.
Sounding better than the stock parts they replace is pretty much a given.