Earbuds for iAudio X5

[Compnewbie01]

I am looking for a new pair of earbuds and the selection is giving me problems.

First, I hear that http://www.newegg.com/Product/Product.asp?Item=N82E16826159208 are good. Second I also hear that the Sennheiser ones are good for the price. Now here are a few links. http://www.newegg.com/Product/Product.asp?Item=N82E16826106311, http://www.newegg.com/Product/Product.asp?Item=N82E16826106400, and http://www.newegg.com/Product/Product.asp?Item=N82E16826106397

The difference I see in the Sennheisers are the Input Impedances. What exactly is this and is more better? Need some information because I want what will sound best for the price.

 

[PurdueRy]

Theoretically the higher impedence might be better as this would allow for a smaller current to produce a bigger voltage drop.

 

[Cerb]

The Sony ones have extra bloated bass, and will certainly break on you (they are also not really normal buds). As to the Senns...
http://www.headphone.com/products/headphones/earbud/
Maybe the 400?

The low impedance could make bass rolloff pretty obvious. I'd really go for KSC75, but if you want buds, I guess the MX400 should do pretty well.