remote start 2008 trailblazer

so i am going to install a remote start in my 2008 trailblazer SS 3SSI was going to use a hornet 561T and add-on remote start to my factory FOB, I decided against it because to trigger the remote start I'd have to get inside the drivers door and tap into the motor wire.... its to hard to get a wire into an 08 door.so i moved onto the viper 5501 which uses aftermarket FOBs...so my question is when using the factory FOBs the reverse and headlights come on during locking/unlocking at night.... if i move to the aftermarket will i lose this feature or will the bypass kit (Fortin INT-SL) help me retain itAny other features I lose if i move to an aftermarket FOB??Anyone have 2 stage unlocking with an aftermarket system... if so what bypass did you use??? the DEI xpresskit or the INT-SL or idatalinkThanks