They are very different styles of headphones. Very hard to compare the two to one another.
HD25 are kind of the bees knees when it comes to quality. They are professional headphones. Comfort wise not the best. You defiantly arnt going to forget you have these on
Bose sound good. Very comfortable. Wireless and noise cancelation.
Now the most important thing im going to say
Active noise cancelation causes headaches. Different headphones designs of ANC have different affects on people. I personally hate the Bose as they give me headaches while my boss loves them. I personally like the Sony version while my boss doesnt like them.
I recommend before anyone buys active noise cancelation headphones to test them. Since your British Ill give you this tip. Most PC world/Currys have the headphones available to try on in their headphone section. Go to a store try the headphones before you buy.