The first time I seen the Gunner, that was it, I had to have one. Picked mine up a couple of weeks ago and it's been great. I'm from Ontario and there are a lot of nice riding around the province. I even plan to do some camping in the provincial parks.
I don't do this on a daily basis, only about 2 to 3 times a year. The added weight was only about 70 pounds, not as much as an adult passenger. There was no problem with handling. I didn't notice the additional weight at all. Mounting the bike is a little more difficult as you can't swing your leg around, but all in all there are no issues.