It sounds very good, as all your reamps
It would be interesting to hear with a mic on the V30 only.
How would you describe the sound between this cab and a mesa?
Although it is comparing apples to oranges because of the different speakers configuration..
I can say that because I have a Mesa with V30s and another one with the same configuration as the Mills you bought. (V30s + GK100s X-pattern) and the sound of the GK100s makes the sound on the Mesa more straight forward, middier and denser.
I have been looking for this Mills cabinet but they ask for US$600 for shipping to Portugal