For those above, I do not argue that an SRW is as stable as a DRW. BUT. There are those who repeatedly imply that unless you have a DRW you will be all over the road and white knuckled the whole time you are driving. And that is just not the case. My SRW/5er does not weave when there are high cross winds. It does not weave when a large truck passes. There is no problem on winding mountain roads. Stability is not an issue. And has been stated so by many others.
If a DRW gives you that much more peace of mind. Great. But don't keep insisting it is mandatory for a satisfying towing experience. And of course, if the weight dictates a DRW that is another matter altogether.