Pros: only about once a year maintenance, doesn't change the look of your bathroom
Cons: water to flush toilet can look soapy
The Aqus is a great system that let's you reuse a lot of water without too much of an overhaul on your behavior or on your bathroom. Not to mention, it's a greywater system that doesn't break any health codes anywhere. I don't actually own one but I worked in an office that had one and it worked fantastically. The only drawback is that your toilet flushing water can look soapy if you use a soap with a lot of suds.