I have used nothing (rented from enterprise) dolly, tow bar and now trailer. The biggest disadvantage to me is taking my coach in for service I hate loading car in trailer, unloading car, unhooking and repeating. So I miss the tow bar for this purpose ONLY!
The advantages are many, I can take any vehicle I want whether it is mine or not, except dually pickups. I can also take a combination of things, smoker, Harley, multiple Harleys and small car, or my Escalade ESV (increase roof height highly recommended). I like securing the vehicle in a dry clean environment, vehicles are clean when I arrive, safe and secure when I overnight in parking lots, extra place to hang out, sleep, or keep the bird dogs on hunting trips (insulated, heated/cooled).
Finding a place for the trailer has never been an issue for me, most places if I must unhook will allow me to leave it on an adjoining spot FREE and I can plug in electricity for lights.
I find most of the negativity is usually from someone's lack of actually using a trailer, as I had apprehension prior to my first trailer. My brother is having the exact apprehension now but he doesn't own anything to tow 4 wheels down.
I have never regretted my trailer decision, I do wish I still had the flexibility for a 4 wheel down plus the trailer as I had prior to my Denali burning up behind my last coach towing 4 down on I-70 and burning up my '99 Eagle.
2009 American Eagle 42'
Trailering HD Road Glide and Saab 9.3 or Cadillac Escalade ESV