It sounds safer to rent a truck and pull a trailer, but I wonder what the statistics are for this. We have a truck/trailer combination because I wanted a safer place to install the carseats (and I didn't think my DH would agree that I could follow the RV with my car). My DH has had extensive driver's safety training (he is a paramedic and is experienced in driving large vehicles), but it still seems a little scary when towing a trailer. The trailers are large and can be subject to sway unless you have a trailer that is within length specifications for the wheel base of your truck. Then you need the correct anti-sway bars and the brake control. There are all kinds of technical details that can be really quite difficult to research properly (and the sales people won't tell you the truth). Plus, it takes quite a bit of practice to properly tow a trailer. I wouldn't want to learn on a rental -- by the time your vacation is over, you are just learning how to tow.
Ok -- I just clicked on the link below. It might not be so bad with a pop up trailer. These are usually lighter and not as subject to sway. I wouldn't necessarily recommend it with a full size trailer or a fifth wheel -- at least as a rental. It will take time to get comfortable with the set up.
I followed my DH home from the dealer the first time we took the trailer off the lot. The RV dealer did not properly install the sway bars, but we didn't realize it! So, about half way home, a semi passes my DH and wow, did that thing sway! I think it may have been one of the scariest moments in my life watching that wild sway. Luckily, my DH knew how to handle the sway, but many drivers would have fought to keep the steering wheel straight, which would have caused the whole set up to flip. The next day we immediately had the set up fixed (by a different place), but I still tense up when passing those semis. The wind sheer can be incredible.