I dunno; I sorta like my JB WElded/RTV Forma Gasket/Gooped Danner:
http://www.voidyourwarranty.net/imag...tus/danner.jpg
Finally got the damn thing water/air tight and it has been a workhorse for months since.
The Danners I believe can produce a bit less pressure than the Eheims, so (esp in a more restricted loop) you get closer to the flow rating of the Eheim than with the Danners. Both are not so great though compared to some other pumps designed to produce some pressure:
http://pw1.netcom.com/~larry_l/pumps.htm