comparing BA immersion programs; please help!

#1
Hello, I am comparing/contrasting a few different spanish immersion programs in B.A. and was hoping for thoughts/opinions. If you know specifically about any of these programs, tell me what you know please! But if not, some advice about their respective locations would be great, e.g. which location do you think is best and why?
All of these programs cost about the same, include a homestay, and offer the same amount of schooling. So i'm mostly interested in opinions on quality of schooling (if you have any idea) and location...
here are the options...
"Latin Immersion: spanish programs in south america", location: Recoleta
"Spanish Abroad, Inc." Location: "central buenos aires" ??
"Bridge Linguatec" Location: downtown, near the area of Puerto Madero
there are other programs, but so far these three look best (though if you know of any other that is reputably good, let me know please).
I'm probably going to do one month of study (I speak some spanish already, but not a lot) and meanwhile look for English teaching work / longer-term accomodations.
which brings me to my last question, unrelated to those above: is TEFL totally necessary for working? I know this question gets asked ALL THE TIME but I can never find a straight answer on the web. I worked in Bogota, Colombia for six months without any certification (at both a university and for a business-english tutor program) and not a single school asked / cared whether or not I had it. Is BA likely to be the same?
thanks so much for the help...-Michael