I have not used a stand alone bidet. What I have used, and loved, is a toilet seat made by a Japanese company named Toto
(You can find them online). They are installed on all the toilets at the Miyako Hotel in Little Tokyo, Los Angeles.
They are not cheap, but the are worth every penny. The higher end models have a control panel (sort of like Captain Kirk's chair) that allows
you to control water temperature, male & female use option (it squirts where each gender needs it to. How smart is that?), water pressure,
etc, etc. I plan on installing them in every bathroom in the house when we do a remodel.
The biggest issue is that you have to have an outlet installed near the toilet to have it work.
Like I said, it's a great product. I highly recommend it.