The Sony EX51sp is of the same 'in-ear' style ear bud but different design and more colour options. It is cheaper and has the same sound quality.
I'm going to be buying the remote for my Zen Micro and I need some help. I'm looking for a good quality, relatively inexpensive pair of earbuds with a short cord. The only ones I've found so far that stuck out were the sony mdr-ex71sl, but $50 is borderline for me. Any others I should consider?

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