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papst and panaflo both make good fans. papst prolly the better made and quieter, but more expensive.
it all depends on what you want really. i mean if all you really want is cooling ability and you dont care about noise you can get a delta. if you need air pressure to push air through a heatercore then the panaflo H1A is a good choice. or the panaflo L1A for a quieter solution.
I like the delta fans myself at full speed you get really good airflow and when turned down a little they are not that noisy.
Yeah you can run any fan off a speed controller just be careful not to have too much current on any one control (the delta's draw 2 amps if I remember correctly).