Depends on the reason you think you might need one.
I have a cheap one because I do not expect to use it often but is useful when needed.
On the ones you mention they all have good cameras but they are 17mm heads so if you wanted to look somewhere where you would need to drill a hole then it would have to be larger than 17mm. Some cameras have 9mm or less heads which can mean they are easier to feed, but the resolution will drop.
The base option is a camera with a flexible head and only live viewing, fine for the quick checking of cable routes and 'where is my cable'.
However if you were doing surveys or had to report findings then a record and download facility would be useful.
The camera only options that connect to a laptop may also be useful as they have more flexibility (but do need a laptop).
Really does depend on how much you are prepared to pay vs the use you may get out of it.
Have a look at the bottom of this page at "similar threads" that may give more information from previous posters.