I just the other day got the viper DS4. Standalone, it is merely a remote start, but has the connectors to be expanded to security system and other features. You can also get 1 way (just starts) or 2 way (confirms car is on and reads data from car) remotes with different range distances. I chose the 2 way lcd model remote. It can show me a confirmation that the car is on, extend remote start runtime length if you got distracted, and even tell you the temp in the car!!! The install time was about 2 hours, and starting price for setup with 1 way remotes is around 350+.
If you are into your phone having control, you can use your phones bluetooth as a remote start controller SUBSCRIPTION FREE. If you want to have cellular connectivity for lets say....starting the car from inside a venue before the event ends, you need to get an antenna upgrade and sub.
As you can see, the options/customizability is extensive. Also, you can technically dump the hyundai fob afterwards or just keep it as an emergency backup. On some cars they can set it up to the OEM fob, but hyundai being hyundai, they did something dumb where that option doesnt work.
