I started my Int'l career at Bolivar in Cali, Colombia. It was a fantastic experience. The financial package is good for Colombia, but does not match the big schools in South America. Still, I had money for travel and saw lots of the continent. Cali is fun city and the people are truly warm and welcoming. Climate is perfect.

American School of Asuncion has 2 reviews on the ISR website. One positive, one not...you can choose which to believe. Staff stay anywhere from 2-7 years.

Asuncion is hot, street crime is no worse than anywhere else in SA, and probably less than many.

SA schools are not for everybody. Many have a high percentage of host country students and that can make life difficult. If you read the posts on this website you can identify common themes, such as pushy parents, spoilt students, etc.
However, even with these problems, schools in SA can be rewarding places to teach. Those same pushy parents can be extremely supportive, and those "spoilt students" can be lots of fun, both in and out of the classroom If you value interpersonal relationships, travelopportunities, etc, SA is a great place to be.