G'day Mate,
I don't know about UK, but here in Australia, mode 1 is the most common, in USA mode 2 is the most common. By all means check with clubs in your area, but it is also a personal thing, I fly mode 1 myself, because I find it the most comfortable to fly aerobatics with, & also it is easier to teach students, on mode 1, I am an instructor.
The split sticks help when teaching, as I can fly using the elevators & rudder, on one stick, while the student has throttle & ailerons on the other stick, I still have control of the aircraft if they over control, this is only for the first few flights, of course, but it does help.