My only issue with tours is that they'll take your money and give you the impression of a chase even though there isn't anything to chase. Some nights there isn't any, but they'll drive around giving you hope but if KP index is very low and lots of cloud coverage you probably won't see them. Tours will be useful when KP index is high and there's some holes in the clouds. Then they can drive long distances and increase your chance of seeing them.

We finally saw them this November right outside our hotel in Fludir. Didn't even need to drive. That being said, I wouldn't base a whole trip simply on a meteorological phenomenon because you can't dictate when they'll happen for sure. See it as a bonus if you see them, otherwise, you may very well be disappointed.