Yate loon?

I have not pourposely bought a yate loon fan...but this is interesting indeed. My power supply has yate loon fans(both of them) and i had a twin fan setup on my chip/ I was removing one of the stickers(it was a cyber cooler) and lo and behold there was a little yate loon sticker. i was wondering if anyone thinks these are good fans...as my knowledge is limited and i dont know if these fans are bad or not. sofar the twin setup(which i have taken apart and using them for exhaust in my case) run each at about 4500rpm and dont suck. how much better are deltas? (that should probabaly be a seperate topic)