I got Senn CX 280s a while ago, which I've been... okay with for the $25 I spent. Newegg has a deal on the Vibe Duos for $20. My main issue with the Sennheiser canalphones was the shallow (if punchy) bass, though the treble didn't impress me much either. Would I see any improvement with the Vibe Duos? Or would I be similarly underwhelmed?
I mostly listen to rock and would use these with my iPhone, unamplified. They're slightly tempting just for the microphone (sometimes I put up with the Apple earbuds for making calls) but that alone isn't enough to make me want to pull the trigger.
I had a V-Moda Faze(seems to look identical to the Vibe) from Newegg last year for $13, not very impressed.
i recently got the JVC FR201 from Amazon, it's the FX101 version with mic, you can get it for about $22(include shipping) on Amazon. The JVC is a hell lot better than the V-moda that i had, it's a lot more clear, not recessed mids, the bass is just stupid strong.
Or you can consider the Philips SHE3575 serie from your local Marshall/TJMaxx store for $10, still beats the V-moda Faze