Okay. It took me about 10 days.
What I like a lot is that I don't need to move my hand. Also the vertical scrolling is pretty nice.
The big, proud ball design is great. You can use a lot of different methods to roll the ball around.
As expected, a mouse is more precise when it comes to clicking really small stuff (Photoshop).
The three things that really threw me off are:
1. The clicks. You need a lot of force to click. I understand that this is because a part of your hand rests on a part of the button, so if you make it light, you'll click a lot by accident. I like a light click, however.
2. The number of buttons. I am accustomed to 5 buttons. Left click, middle click (Linux user), right click and back+forward. The Slimblade has only four buttons, and I'm stunned how much I use the forward button.
3. Horizontal scrolling. I use a Logitech MX Master in my office. That lil thumb wheel is really handy with spreadsheets. Navigating to the horizontal scroll bar and pulling it around with the trackball is not as much fun.