We have a Flagstaff 21WRS V-Lite. So far we have not had any issues pulling it. We bought it primarily for two reasons, 1. We love the layout and 2. It is light enough to tow with our 1/2 ton Chevy pick up.
My experience with dealers is that, if you ride in on a bicycle, they will tell you that their trailers can be towed with a bicycle (LOL).
IMO the V nose shape probably makes the trailer a little more aerodynamic at 60 mph, but There are many other things to consider when towing (i.e. weight, length of trailer vs length of tow vehicle, weight distribution, sway control, etc...) that will have a much greater impact on how easy or how safe it is to tow any given trailer.