I didn't do this program specifically, but I went to Antigua prior to 1st year. I don't really have advice, just my experience:
1. Guatemalans are really chill and sweet people and I felt safe down there (exception: Guatemala city is dangerous). I did some course where they teach you up to 8 hours a day (too much). The teachers were top-notch.
2. Antigua is much more touristy than you would be going, which could go either way. I personally would have preferred going to the boonies since Antigua was kind of a party scene and there were a bunch of other white people hanging around. I had friends that went to Lake Atitlan and absolutely loved every minute of it. You might want to consider malarial prophylaxis though (although Google tells me you don't need it for Antigua and Atitlan).
3. I went down there thinking I could pick up the language in a few weeks, and needless to say my confidence was crushed. Either way I picked up more Spanish in 3 weeks than I did in an entire semester of college. If it were me, I would do the 8-week deal, and give myself time to absorb some of the nuances of the language (there are like 5 different past tenses, lol)
4. You can't go wrong with Guatemala. If you can get the trip funded that would be an incredible experience. The Spanish down there is very similar to Mexican spanish spoken in the border towns (and the states for that matter), except it is a little more formal. This would be helpful since you want to be able to use more back in the states. Plus, the people down there are dirt poor and sincerely need help. You know, that whole altruism thing.
