I have both the DT880 and SR225,I end up using the DT880's about 90% of the time. Most of my music listening consists of progressive and hard rock.
The SR225's (which I have owned for close to 12 years) do rock extremely well but can be somewhat fatiguing both in comfort and frequency response. My ears feel like they are burning after an hour or two of listening and the upper mid and high end can be grating with extended use. I have yet to run into a headphone in it's price range that reproduces an electric guitar as well though. The SR225 also has very good bass response when it comes to speed and complexity of a kick drum and bass guitar, but it does not reach very low.
The DT880s are extremely comfortable. I can wear them for hours with absolutely no fatigue. The sound signature is not as exciting as the SR225, but it is very balanced. The frequency response is for the most part flat. They do have a bit of a boost in the 7khz-9khz range which can make them overly bright if paired with the wrong equipment.
From what I have read the DT990 has more low and high end than the DT880. It may be better suited to rap and would still work well with rock. The SR325 is supposed to have better bass than the SR225 but is also more fatiguing at the upper end.