Thanks to everyone that's replied. It's giving me a lot to think about.
I guess the main issue is that I don't have unlimited funds. A dolly cost is pretty low and easier to get going as compared to 4 wheels down. By the time you figure the cost of base plates, tow bar, wiring harness, labor, aux braking, etc, etc, etc, it gets to be pretty substantial. And for the most part, that's to get only one vehicle ready to tow. A tow dolly, while more cumbersome, handles any/all vehicles that I can put on it.
I agree that towing 4 wheels down is the best, but it's not necessarily the best option. Unfortunately, I'll have to choose between vehicles .. or resign myself to removing the drive shaft on the Jeep each time if I decide on the tow dolly for the Jeep.