Thought I would mention that husband myself and son went on the buggies with Bali Quad. We had a fantastic time and found the buggies great fun. We got really filthy dirty (and it wasn't raining)from the mud but were able to wash ourselves when we got back (they supply towels). I thought the meal provided was good also - soup, 2 curries, rice and fruit. While both son and husband are experienced bike riders they chose the buggy over the quad bike and were pleased as they could concentrate on where they were riding and not worry about managing the bikes.
The downside for us is that there was a group of 4 Russians sharing 3 quad bikes and one of the riders had no idea and was forever stalling the bike and holding us up. One of the other quad riders also kept videoing as he was trying to drive the quad, which seemed pretty dangerous. The guide kept the quads in front of us and it really slowed us down as well as being very annoying to get half way up a hill and then stop because they couldn't manage the gears. We also had to stop for cigarette breaks which I thought was annoying, when we didn't smoke.
The scenery was really great and overall a great experience. I am nearly 50 and had my own buggy and had no trouble at all, so if you have ridden a go-kart before, give this a go - it is even more fun.
I did worry about the impact on the villages and people taht we rode through becasue of the noise and fumes but everyone seemed to put on a happy face, so I was hoping that they really didn't mind.