I have one of the original Reserators (not the Plus model) and it works great. Despite what others say, silent fans are not silent. They are silent only in that they aren't louder than the other fans in the case. But anything that cuts down on the # of fans in your case will reduce the volume.
The reserator isn't simply as quiet as a fan, it's totally silent. So your CPU and GPU don't have any fans at all. It's not ideal for overclocking but it sounds like you just want a really quiet system and it works great for that.
Keep in mind that you don't need as many case fans active if you aren't trying to vent the heat from the CPU/GPUs so that makes it quieter still.
One other thing to consider if you want quiet that rarely ever gets mentioned is the motherboard fan. Most motherboards have a tiny fan on them that makes a lot of racket, much more than all the other fans combined. So buy a fan-less motherboard, especially along with the Zalman and it will be nice and quiet.