what is better and why?
Rarely can go wrong with Corsair. I've yet to see them enter a market without some work behind it. Their water coolers are pretty great, and while others may have better performance or be quieter or cheaper or whatever factor, Corsair is a US company that puts high quality into their work with solid customer service. That's worth it to me!
I'd go Corsair because they have been doing AIO water coolers for a while now. The fans they use a very good, corsair link is a nice feature (if you get a model that supports it) they have a good warranty and I actually haven't ever heard of one of their coolers failing. And then the cooling performance is constantly good across their products, if you buy the right cooler for the job that is
I just seen the vid they have on newegg.com and I like what they are saying with that feature. I'm looking at the Hydro Series H100i
Thats a very good cooler, highly rated