As Cathar has said, if you're going with an Iwaki 20 series pump, the RZT is the only one to consider. You might want to consider paying the premium in order to get the Japanese motor, as there is a noticable difference in the noise level and operating temperature between the two.
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Michael E. Robbins
M.A.Sc. Candidate, University of Toronto
12.1 GHz of AMD's finest (17.7 GHz total) crunching proudly for the AMDMB.com Killer Frogs
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