I actually think theres just more people with coolit than corsair ones tbh, hence the higher number of defects. I reckon between the two theres roughly the same defect rate though, and its still pretty small.
To clarify - Coolit do NOT own Corsair, and Corsair do NOT own CoolIT.
CoolIT however are the manufacturers of all Corsair coolers. So if you buy a CoolIT product from us, it will be very similar to the Corsair model, but cheaper.
About leaks - earlier CoolIT products did have some occasional issues with leaking. However, we have not had any reports of ECO II products leaking and we have sold 1,000's.