I collide Bullet Journal with my filofax (knock off paperchase version).
I print my own inserts for it, so have pages set up for the monthly page etc to save me writing it out and drawing boxes etc. I also am able to add in blank pages to the weekly bits if I need more space.
I then keep collections, or unrealted lists to the planning aspect of it in a different section and can move stuff round as I like. I also have a meal planner and shopping list page for each week, food and exercise tracker, short and long term goals page, task prioritisation + page for when the daily/weekly list gets too long or overwhelming.
I have various dividers and sections with different coloured paper etc.
The only real difference is the index, mine is a bit more fluid as I can move things to suit.
I find it a bit more flexible than a linear notebook. I don't find having the printed pages as restrictive at all, more that I am organised as the pages I need are sitting in the wings waiting for me to use them. I don't need to wait to draw out the layout to get on with it.
It's working for me so far. I love the look of so many that I see, but in reality know I would get bored and wander off from it if I had to stay true to the original system.
I do still use Google Calendar on my phone for appointments etc, but see my physical diary as a get shit done helper.