I believe the Mancini Racing Water Pump Housing is the standard in affordability, quality and reliability. I have owned 2 (2 different 440's). The 440 source got some flack in the past but they fixed the issues and are a quality piece now and a little cheaper than Mancini. Mopar Performance is generally regarded as good but over priced. PRW I have no experience with, but if Marsh is selling and standing behind them, then I would definitely consider buying one.

When it comes to mechanical Water Pumps, Ill always buy Flowkooler. I believe they are the best compared with others in the price range. FYI, the Flowkooler pump fits perfectly in the Mancini housing. I had a thread a while back showing the fit and clearance of my Mancini/Flowkooler combo.