I've used all (3) at different times and I can honestly say that I definitely do prefer charcoal.
Now, when it comes to propane vs natural gas it gets a little iffy... as I've powered by BeefEater from both sources at different times.
At a couple places I've lived you could tie on to the main line for gas... so no need to ever fill a bottle or run out during a cook.
Propane yep, it's portable and I do find that it burns a little hotter than NPG too.
At the end of the day, since I'm not gonna haul a gas grill around everywhere I might lean towards the natural gas just for convenience, but I really haven't found much difference in the final product that came off that grill as long as you adjust your settings properly for each fuel source... my BeefEater gets hot enough to sear steak with either type so not much of a trade-off losing the extra bit of heat. The only time I was happier on propane is doing turkey at Christmas with the wind up and roaring... that open bottom grill can use the extra btu's in those conditions, but it never let me down... just took a little bit longer... that's all. :-D