We booked our northern lights tour with Juki tours, and it was the best choice of our trip!!!
When we booked, our tour was set for our first night in Levi. On that day in the afternoon, we received a message informing that due to the bad wheather conditions, our tour would be postponed (we stayed at Levi for 6 nights, and let all nights as option for the tour). 3 nights later, we went on our tour. From the apps and wheather conditions, our changes were low, since the activity wasn't so strong, and it was really cloudy. Our guide Simon, drove us away from the clouds and we had a wonderful night seeing the auroras!!!!
Couple points about Juki tours: they really do take you to the tour on the best day possible, and make a lot of effort to get you to see the northern lights! Our guide Simon was a good driver, nice talks and took amazing pictures! So also as a plus, they take a camera with them, and the pictures are included in the tour. One last point is that we where back to Levi around 00:30, and by 9am in the morning I already received all pics on my email :)
Strongly recomend them to anyone who wants a better chance to see the northern lights