Without knowing too much about the gaias, it seems like they work like a shock absorber or even springs on a car in terms of downward pressure the weight places on them. So, imagine you have a small set of springs and put a medium to large dump truck on them. They may or may not hold up the truck, but it may not be a smooth ride along bumps or steering etc...
That is how I view the gaias and their weight capacity. I got the #2 just to be safe, although I was tempted to get the lighter capacity ones.
It's not about breaking or holding up the speakers, but the footers doing their job in a capable way, instead of being overwhelmed by the weight.