In one respect he's right. The quad has solid drive on its rear tires (no differential) so that when you turn the machine on a nice grass lawn, the inside tire will be turning at a faster speed in relation to the grass it's passing over and it will rip it up, regardless how carefully you turn. The other arguements are all subjective and depend more on the rider than the machine.

 

if the rider is careful, an ATV won't hurt the land anymore than a dirtbike. I think that ATVs are safer too. Just my $.02.

 

Well whats safer really depends on where your riding. If you go up a steep and long hill on a dirtbike, and loop it or fall over 99% of the time the 2 wheeler will just stay on the hill. Loop a quad on a hill and the people at the bottom need to move.

 

As a dad, and an ATV'er, and former dirt biker (I got too old, lol), this is the way I see it: the ATV is harder on the lawn (stay off the lawn whether it's a bike or quad), the ATV is better in the mud, the bike is nearly useless. Fun factor? When the weather is good, it's the bike all the way.
Dangerous? People may not agree with my opinion, but on equal terrain and driven in the same fashion (fast and aggressive or slow and easy), the bike is the safer of the two. Granted, you will dump the bike more often than the quad, but the bike weighs 200lbs. A sport quad is 400lbs and a utility at least 600lbs. The bike usually goes down and stays down; quads seem to have a built-in-brain that causes them to chase you down and roll over you when you dump them (it's revenge, I think). If you flip a bike back over on a steep hill climb, you push it out of the way when it comes back over. When the quad comes back over, you scramble to get out of its path when it tries to body-slam your lifeless carcass.