Neither obviously vibrate. The idea behind dual opposed is it stops the cabinet/subwoofer itself from moving at all. Its stays sturdy and doesnt move around your room. The drivers are very strong, and the pressure changes inside the cabinet cause the panels them self to vibrate. Good bracing is what helps eliminate this.
With this sub and mine, you can feel this vibration when you put your hand on the side, but there are no visible signs at all. You can put a drink on the sub and at full power it barely affects the drink.
I would quite happily put a tv on top of either and it wont fall. At full power you might be able to detect some movement up close, but I doubt you would from the viewing seat.
I'm going to take the fourth on this one though, as if you try it and something was to happen, there are to many variables in your construction for me to completely rule out it being a bad idea. Saying that, I know I wouldnt have an issue with my tv on my sub.
Hope that helps.