Fan recommendation for XP90 on a 3800 x2

[NaOH]

I have a zalman 92cm fan on there right now and I idle around 37C and 50C under load. Seems high for stock clocks. I heard panaflow was good and the tt silent cat, what is the best fan I can get with the most cfm? Noise is not a problem.

 

[RallyMaster]

Sunon?