Pros: Lightweight, great sound, low price, easy to power, comes in nice packaging, looks clean, compact, fairly comfortable.
Cons: mostly plastic build but its perfectly fine. The sound is quite astonishing for the $55 paid.
These headphones are a steal at the price I got them at. Sennheiser has a standard 2 year warranty on them when registered. There's nothing bad to say. Honestly, if you want a pair of travel headphones that sound great without breaking the bank, these are the way to go. I was a little opposed to the idea of on-ear headphones but these are pretty comfortable. I'm no sound expert but these easily score a 4.5/5 in my standards.