Pros: Clarity, emphasized midrange, lightweight
Cons: Lackluster bass (stock)
Paid MSRP at baybloorradio.com, which has a high markup. Picked these over the SR325is because they were significantly lighter. Reviewed with a Nuforce uDac.
Audio: What can be said about the Grado house sound? It's a love-or-hate intimate style. Electric and acoustic guitars simply rock on this headphone, as do instrumental pieces with few key instruments. However, the bass is rather anemic at stock.
Design: Being lightweight is good. However, free rotation of the cups is an issue, and there is crimping on the cable near the Y splitter. The left side gave out after 2.5 years due to this crimping, but the fine folks at Ring Audio (http://www.ringaudio.com) repaired it nicely.
Comfort: I find them quite comfortable, but I have small ears. They are amazingly light at 200g, and if you wash the bowl pads to soften them up, they become even more comfortable. People like to complain about the vicegrip clamp out of the box, but it's easy to bend the headband to your desired clamping level.
Recommended buy if you are aware of the bass deficiency and can work around it.
EDIT (Aug 2011): The bass (and as a result, audio quality) can be improved greatly by using the vent mod. This is preferred over taping the bowl pads since it won't muffle the midrange. By venting 7 small pinpricks on the felt around the driver, the bass of the SR225i increases to the point where it's slightly less powerful than that of the HF2. Of course, if you prefer even more bass, you may vent all 10 holes and make all the holes larger. The star ratings for audio quality and overall reflect the sound with the vent mod; -1 star at stock.
EDIT (Feb 2012): Decided to vent all 10 holes, then enlarge two of the pinprick holes all the way. Wow! Now they sound almost as good as an RS1i, and so sound quality and overall rating are now 5 stars!