Conclusion: I was so impressed with the Grado SR-56's that I didn't hesitate ordering the 125i's. Though I feel the 56's have better balance in the entire frequency spectrum and are the best headphones I've found in their price range, the 125i's stronger high end response and detailed, solid bass at double the price, have grown on me over time. They are especially well-suited for acoustic and classical recordings. Like the 56's, they are light and very comfortable to wear.
Summary: These babies can sing. That's all I can say. I had never tried a pair of Grados before these and I'm pretty shocked (in a good way.)
The box leaves some to be desired, a pizza-box style box, with an image of a pair of Grado woodies on it. It has a GRADO headphones name in vintage-ish blue/purple/orange, and a quotation reading "truly the world's finest.
Pros: Sound quality, Surprisingly good build quality, works unamped and shines even brighter with.
Summary: These headphones are quite good, and have really great highs. They are an improvement over the SR-80i, with a more balanced and bright sound with better articulation. For the money, they are quite good.
These headphones do need to be broken in a bit. The highs start off a little harsh and tinny, but end up pronounced, but more balanced. They also need to be amped to get the full sound. Without an amp, they are dead.
Pros: Very good mids and highs, crisp bass, good articulation, no distortion
Conclusion: These headphones have been nothing short of fantastic. Just like many of the other reviews will tell you, they are incredibly clear, detailed, full-bodied with a slightly forward sound, which is really live. (without being artificial) Easily powered by my Cowon S9, X-Fi Xtreme Music, and Kurzweil SP2X. Construction is solid, those cables will never break. Ridiculously comfortable, even with my glasses for hours. Top notch buy.
Summary: I originally bought a pair of Grado GS1000e for £1000 but they arrived with a distorted earpad, I tried them out and the sound quality, in my humble opinion, was not worth the money so I returned them. I then tested out a bunch of pairs up to £300 at Richer sounds and the Grado SR125i were joint best with some Bang and Olufsen Beoplay H6. So I went on Amazon and got both pairs for £300 quid!
Summary: Initially I was going to get the SR80s but having read the reviews across a range of forums I opted for these wight he price much cheaper than at my local dealer. Delivery was much quicker that originally advised so top marks there. The packaging IS very basic but hey, it doesn't affect the quality of the music you hear. The sound quality is fantastic with really clear bass - but I don't know if the 80's would be just as good.