Product review (5 stars): Every house needs this...
This is such a "why did I not have this before now" item.  We also have houses that we rent and you can bet I will be putting this in each one.  Having the peace of mind that the water will shut off if there is a flood about to occur is priceless.  The leak indicator is a nice touch but I probably would not think to check that so the automatic shut off feature is invaluable.  The downside is that install was tricky since the hose was a bit stiff.  I too had to make use of a wrench every so lightly even though it says not to in the instructions.  Hopefully you will not need to use one.