I recently (just over a week ago) picked up a pair of Sony ED21LP headphones for just under a tenner. If you shop around online you should find prices close to that.
It's the second time I've had these particular models and was instantly impressed for that second time!
They're old designs (had my first pair around 1998) but are little crackers in my opinion.
Great bass, pretty good imaging and decent isolation too. Only issue I have ever noted is that they can be somewhat ear specific due to the bass port that pokes into the ear canal... for example my Mrs couldn't wear them as her ears are quite petite and yet for me they've been absolutely fine.
In the past I've had Gummies, Sennheiser buds, other Sony buds (specifically EX71's and EX81's) and even some Ultimate Ears Metro Fi II's. The Metro's were the only ones of those listed that bettered the ED21LP's - but they should have since they were about three times the cost.
Oh, and as for Skullcandy ear buds - if the majority are made like a set I bought at the start of the year then I wouldn't bother. Got them for my Mrs for a trip to China and they broke before she even set off. They had perhaps 8hrs usage maximum.
I honestly wasn't surprised though since they felt very flimsy when we first took them out of their packaging. Of course it might be a one off. We've got a set of full sized Skullcandy cans which have been used for 4 or 5 years without any issues. I suppose it's the chance you take really!
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