First of all, something of a disclaimer: I received a massive scholarship for this program. Now, this goes both ways; my own experience was of a massive bargain, which I cannot imagine is shared by those who paid the full $8000 or so dollars, and is not the average experience; on the other hand, you can see that the scholarships for this program are very generous. I believe most of my classmates received some sort of financial aid. Personally, all told, I paid about $3000 dollars for this two-month program, including housing, a variety of daily language-learning classes, and many extracurricular lessons and excursions - although keep in mind airfare and food is NOT included, the first totaling something like $1000 each way and the second something like $500 for the two months (there is no school cafeteria, but as a college town, food is accessible and cheap).
Now for, in my opinion and that of all others in the program whom I asked, the best aspect of this program: the education. The teachers are actual Taiwanese people, almost entirely women, equally versed in the Traditional Chinese used in Taiwan and the Simplified version of China which I myself study (meaning that one can just as easily study one as the other), and who are all fluent in English and passionate about what they do. I've heard it often said that the best language teacher is one who does not speak the native language of their students, and certainly we all benefited from bans on speaking anything other than Mandarin, but I'd add the caveat that the best language teacher is the one who does understand the language of their students but refuses to use it. This bilingualism meant that as we struggled to translate phrases too literally from English to Chinese, these teachers could understand what our meaning was in English and tell us the proper Mandarin saying.
Aside from the classes one would probably expect - every weekday there's one on grammar, followed by another on new vocab and reading comprehension, and both focused strongly on speaking skills - there was also something of a poly-sci class held in very small groups (max, mine had three people) in which we discuss problems in the modern world that effect both American and Taiwanese peoples. On top of all that, to start off the day we had hour-long individualized tutoring sessions with graduate-school students working toward their teaching degrees who were just as talented as the full-time language teachers we studied under for the rest of the day. The teachers are so lovely, shockingly young - were any even in their thirties? - and a mix of strict and understanding that I've actually never experienced before. Although, I will say - you will spend most of your time studying. Be prepared: this is not merely an easy way to explore Taiwan!
We had many excursions, my favorite of which was a visit to a small island off the southwest coast where we snorkeled with endangered sea turtles. A warning: although I didn't really mind, every class, every activity, every excursion, is required (unless otherwise mitigated by health reasons), which many of my classmates found stifling. They often compared it to a summer camp rather than an academic program - although again, that was a complaint only about these extracurriculars and not about the rigorousness of the classes themselves.
Two months is a long time, and in a city without great public transportation, yes, it sometimes became a little stifling. I certainly was very homesick for nearly the entire trip. Many everyday problems will come up, which are exacerbated to a massive degree by being on the opposite side of the globe from your hometown in a city small enough that many businesses institutions survive without any or minimal internet presence (which makes looking things up very difficult) and surrounded by people speaking an entirely different language from your own - and in my case, using even a different writing system (remember, Traditional Characters!). Sometimes, yeah, when I asked questions of teachers and other program officials, they seemed confused by my inability to find things online and thus were not terribly helpful. So you will indeed need to be pretty self-sufficient. But hey, even those experience I would not trade for the world! A program like this is not merely about studying language in the controlled classroom environment of the weekday, but also the learning to how to navigate totally foreign situations totally on your own, without parents, without teachers, often even without friends or classmates to buffer to awkwardness that will inevitably arise as you repeat your drink order for the fourth time, clueless as to which word you are pronouncing wrong since the server is clearly not understanding.