As a practical proposition for touring the Tri-pacer takes some beating.
I have a share in a PA22-150. It cruises at 100Kts at 30l/hr, will lift full fuel and three adults and take them more than 250nm from their starting point (with reserves).
The undercarriage is rugged and copes happily with rough strips. They can be well equipped.
But it's not a practical proposition for touring with four adults. To lift four adults you will need to reduce the amount of fuel on board to the point where a bimble about in the local area is all that can be achieved.
As a 'head turner', well, the heads won't turn very fast, but people are interested in Tripacers, if only for their slightly quirky looks. They do get people talking. I visited Defford recently and met someone who had jumped out of a Tripacer (with a parachute) - Tripacers are certified to fly without the rear door for parachuting!
UA has outlined all the quirks. The rest is all brilliant!