I have been a minimalist/barefoot runner for 4 years and have run a 50 mile ultramarathon and am currently training for 100 mile ultramarathon. I am constantly asked how/why I do it and the best answer that I can come up with is because I like the way it feels. I feel light on my feet and strong. That being said I would only recommend someone to use minimalist shoes if they truely believes it will be better for them over the long run. When I transitioned it took me 4 years of have sore arches, achillies, and calf musles. Because of this inital pain most people use this as proof that it is bad for you. I spent a lot of time with rollers working out pain in my legs. My muscle and tendons have now become strong enough that I don't get pain. In the last three years I haven't once had a running injury and I average around 50 to 60 miles a week.
I view minimalist running as a long term benifit to me. I want to be able to run into my 60s and 70s. I have consciously made the gamble that minimalist running will allow me to do that. Time will tell if the gamble pays off or not.