I liked a wired connection because it is secure and, in my case, results in a much stronger signal going to my device. I am not able to receive a any wireless signal in my living room. While I know that I could use an range extender, I prefer not to for security reasons. My two computers, printer, television and Blu-rRy player are connected to my router via an Ethernet wired connection. While I have been unable to test the sonics, I know from hearing other people that a wireless connection sometimes drops the signal.
I know that a wired connection is stable and a reasonably fast connection. Because my router is on one end of my home and the Blu-Ray player on the opposite side, using a wireless signal is not possible.
Assuming that both a wireless and wireless signals are strong, my assumption is that the sonics are probably going to be the same (I really do not know). However, in my case, I prefer the wired connection for security reasons. Let us assume I could receive a wireless signal in my living room. I would still use a wired connection for security purposes.
I was not able to easily run an Ethernet cable from my router to my device. After some research, I connected my Oppo Digital 105 Blu-Ray player to the Internet using an Ethernet over power-line connection (uses your existing power-lines). It has proven to be a very reliable connection. Connection problems are very rare. My video system, dishwasher and other home appliances do NOT interfere when I am using the Ethernet over power connection for my Oppo 105. I am using the ASUS home plug AV power line adapter kit PL-X32m rated at to 200Mbps (Ethernet over power-line).
There are many other Ethernet Adapter brands on the market but the ASUS PL-X32m works. However, I am thinking of replacing it with the Linksys Homeplug AV2 Powerline Kit PLEK500 (no decision yet). There is no noise problem with the Ethernet over power since it runs on your electrical lines at a higher frequency than the electrical power.
I found the two links below discussing wired vs wireless. See:
http://www.computerweekly.com/feature/Wired-vs-wireless-in-the-enterprise
http://www.zdnet.com/blog/igeneration/wired-vs-wireless-security-vs-speed/624
I hope the above answers your question.