Never heard of them. Nice looking website; looks like a pretty sizable dealer. The real question is; what do you want to replace it with? Assuming you want to stick with OMC/Bombardier for controls, harness etc, I would avoid any late 90's to early 00's OMC engines or anything that was Ficht or Ram design. Next do you want 2 stroke or 4 stroke? Carbs, EFI, or DFI. I would definatley shop for some kind of warranty. The good thing about newer engines is that they can talk to you by downloading the ECU to get hours, average run RPMs, basic history assuming everything is original. If the dealer is reputable and honest he should share the engine data with any hesitation. I would rather buy a clean original engine than one that someone has been inside of. The main reason is because there are different definitions of what rebuilt is. They should be able to share with you what has been done to the engine including the exact parts that were replaced tied directly to that engine serial number.
