I am currently running a EuroReef CS-1, an AquaC Remora, and an AquaC Remora Pro on various tanks. I would go with EuroReef hands down if I had a sump on the tank. The only reason I see to use a Remora or Remora Pro would be in sumpless applications where they are the best of a bad lot.
The EuroReef is constructed much *much* heavier duty, and pulls tons of skimmate. Every time I service one of the Remoras I worry about breaking it, and the skimmate is nowhere near the quality I get with the EuroReef. The preskimmer boxes are a pain, and they have to be dismantled and cleaned way too often.
I got my EuroReef as a 'blem' from
http://www.h2otropicals.com for nearly $100 less than retail and cannot even *find* the blemish. Upon checking I see that the site is under reconstruction- it is definitely worth checking around to see when they will reopen.