Summary: I've own/owned every single pair of Grados except the PS1000's. In general, they're great. But the only ones to disappoint are the iGrados (which were a joke), and the SR125.
If you look at the freq. graph on headroom, there is a strong dip in the midrange near the 5KHz range, compared to, say, the SR80i or the SR225i. What the... Grado?
Midrange consequently ain't too great. I'm not saying these are horrible, just not the typical Grado sound you'd expect.
Pros: Relatively cheap, comfortable pads.
Cons: Strong dip in the midrange frequencies, the SR80i sounds better for less.
Summary: Good sounding phone. Bass is controlled, somewhat light, and in no way overpowering. Highs are tamed a bit over the lower models and detail is brought out more.
The 8 Cond "i-Cable" is a little bulky, but the advantage it gives these over the SR80i is worth it.
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