Well, all I can tell you about my experience is that I had to replace both front calipers shortly after buying the old Jazz, but the rear ones have been fine, and they look original.
I fitted cheap pattern ones, and they have been absolutely fine - but I think even I would have been swayed by a genuine caliper at that price. Dirt cheap.
As culzean always says, changing brake fluid regularly is the best way to preserve the life of your brake calipers - preferably every 2 years.