There isn't much to add to the qualities of the Sennheiser HD-25 and its variety of models. Instead of writing a complete review which there are plenty already, I will try to answer some questions that I had before buying the product.
The package of Sennheiser HD-25 Plus comes with the HD-25s installed with coiled cable and pleatherish earpads, spare pair of velour earpads and a spare 1,5m L-jack straight cable.
The build quality of the Sennheiser HD-25 Plus compared to the older models is virtually the same. At first the product feels flimsy but in longer run it will prove how unbreakable the build and design really is.
The great thing in buying the Plus version of the headphones is that you already have a spare cable when your cable will eventually wear out as is the case with the HD 25s usually.
The sound of the HD 25s is quite warm with ridiculously deep bass. The mids are very present and the highs are quite tame but still there. It feels that in some songs the bass can overwhelm the highs just a bit.