You may find yourself to be biased one way or another as well after hearing the four of them. I'd strongly recommend making a trip to give all the options you are asking about here, and hopefully even some others, a proper audition with a large variety of material you are very familiar with before pulling the trigger.
There are a lot of other options out there as well that you may have or may have not considered that you may like even better. Lines from PSB, Revel, Focal, etc..
Where are you located? Maybe I can help you find a dealer within a reasonable amount of driving distance. Maybe someone on the forums who owns some of what you are considering nearby would be willing to let you have a listen.
That's a pretty substantial investment to buy solely based on what other people have to say about it. To me it's always worth it to do whatever it takes to give them a proper audition before pulling the trigger to make sure its' something you'll be happy with. Opinions are like ********, everyone has one.
I'll talk briefly about the KEF XQ30's as they are the only speaker you are mentioning that I've auditioned. Take what I say with a grain of salt, because what I dislike you may like immensely. I found the sound of the XQ30's to be a bit forward in the high end of things. I like to listen to some heavy metal guitar solos at pretty loud volumes, and found the higher guitar notes and cymbals to be a bit over-emphasized for my tastes. I reached ear fatigue/pain pretty quickly with these compared to other speakers. I also felt the bass sounded a bit drier. They didn't have the rich, accurate fullness that I love so much. The imaging when sitting in the sweet spot was very good but trailed off very quickly even just a couple feet out of the sweet spot... more so than most speakers. I am certainly not a professional but these were my first impressions with this speaker.
