I've read the 3rd generation Smarts (16-17) are actually quite the improvement over the previous generation and much more "car" like features and feel to them. Certainly smart cars aren't most people's top choices when it comes to cars, but there's definitely an advantage to being able to carry a vehicle sideways on your truck.
They certainly are other options of you don't want the Smart. The Smart is the only car that's capable of fitting sideways on a rig, but plenty of others have carried Trackers/Jeeps or other cars lengthwise on their rigs. This does greatly extend the length of it. Jeeps, Trackers and other 4x4's have the advantage of being able to climb ramps to make their overall length less of an issue.
This isn't the best setup I could find, but you get the idea of what you can do with a 4x4 vehicle to carry it lengthwise.
Smart Car 2nd gen vs 3rd gen
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