Check your manual - or if not available talk to your Highlander dealer - for specifics on the frontal area of the Highlander. Over the years, Highlanders have not been known to be sensational tow vehicles. Having one of the smaller HTT is a benefit, but not to say that you are good to tow it....yet. Need more info.
You say mostly towing in AR....the flatlands or the hills? Big difference.
Our old camping buddies had a 6cyl 4-Runner and a Shamrock 19...they were less than thrilled and made a change to the 8cyl. Much better. My gut feeling is that you should likely be looking at a 4-Runner, 8cyl. A bit more $ to begin with, but if you find you have too much trailer and not enough tow vehicle, you'll be out more $$ in the long run. Riding in both of their 4-Runners, we didn't feel that the ride was uncomfortable at all.
