Hi, Richard. If you read some of the older posts about commercially-made tables of various brands, and router table designs for shop-made tables, you'll get a good sense of the range of features and uses.
Bench-top models have obvious limitations, including which routers fit the pre-drilled mounting holes, and often, the size of bits that can be used. Some have lifts available, which allows above-bench bit changes, easy adjustment, etc., some don't.
Ultimately, the choice that is right for you depends on what you want to do on the router table. There's no easy, one-size-fits-all answer.