[mvanvoorden]

It's definitely not the same as relaxing on a beach for 10 days. Not even closely similar. Yes, you might be more relaxed, but this meditation is hard work and really disciplines your mind, something you won't be doing on a beach. As far as you are even aware of how active the mind is all day long, the beach will be full of distractions and you would take any opportunity to avoid any uncomfortable situations as well as take any opportunity to do things that give you short, momentary pleasures.

I noticed the culty part about it as well, but it makes sense to me, because it really works. The claim they make is really met and this convinces a lot of people that everybody should at least once in their life do such a retreat, including myself.

There is the Vipassana Research Institute, but their website disappoints me a bit, because the amount of links that is actual research is quite meagre. There are some good results with Vipassana in prisons, though. See http://www.vridhamma.org/Home.aspx