Been using artlantis for 20 years the biggest advantage is real time changes to the model inside artlantis when you add a texture or a light you see the effect without having to render the scene, it's also easier to bring in external 3d models, cars and the like come in perfectly in a variety of cad files and the trees are fantastic, batch rendering is a breeze
1. What is the overall quality in terms of photorealism of the renders when comparing Artlantis and Vectorworks? I WOULD SAY THE SAME BUT EASIER TO ACHIEVE IN ARTLANTIS
2. Assuming hardware is equal, which is faster at high quality renders? VARIES
3. What is the learning curve for Artlantis when compared to Vectorworks? EASY
Hope this helps feel free to contact if you require any further information