On the topic of changing LODs and headphone cables.
I have compared the fiio low profile LOD, a solid silver LOD and a picolino silver LOD and there is indeed more treble information and sense of space in general. But the fiio products certainly are not totally outclassed.
Chrishimself made me a silver LOD quite some time back and it was a bargain compare to the big name brands. If you want something that I think is a work of art then check out the cables and LOD's made by Qusp. Seriously nice in my opinion.
Upgraded silver headphones cables will make a similar change to sound. Silver may sound bright and this innitially makes the bass seem withdrawn slightly but once fully burned in the top end will smooth out and the bass will be a little snappier. I was amazed at the improvement that a silver headphone cable did to my old Triplefi x's. They were transformed from a bass heavy and slightly mid lacking iem to seriously closing the gap towards the quality of a custom. I would never own them again without a silver cable. They were that much nicer.
And lastly. Copper cables tends to favour bass. Silver is more top end change and silver plated copper tends to be a combination impact. Who would have thought!
These are just my own personal observations from my own playing with headfi gear. Hope it helps. Cheers.
Also, see the sound science subforum, for more information on this topic - and on the issues involved in objectively measuring, and evaluating the effects cables do or do not have. As with anything, do your research before spending money.