re: Choices
It was safe for the landing, it enables the Rover to travel around and explore more by going faster or further.
It's supposed to be an ancient lakebed.
This kind of terrain is what scientists have been waiting to study.
If the team of Spirit scientists will be happy with the results, then we should all be grateful Gusev was the right kind of choice.
But it's true, there are no high mountains over there, or at least it doesn't look so.
On the Moon, the astronauts had the utmost difficulty in judging distances. From the 4 Mars landscapes we know, now, judging distances was also a challenge! The horizon must be at 4 km distance.
Raoul