I was a heel strike runner for years. Perhaps I'd been given advice as a teenager, but ignored it in favor of the advice Nike was giving me in the form of fancy air cushioned sole shoes which encouraged long stride heel strike running. Formation runs in the Army, continued to reinforce this style of running, matching cadence (stomping feet and shouting jody calls seemed more the point of those runs than actual PT anyways). I developed knee problems by about my third year of enlistment, which followed me for years after my ets.
I bought my first pair of VFFs about a year and a half ago, after spotting them in a WOD pic on the Crossfit website. I have found Crossfit to be a very effective fitness methodology, and had also been learning Tai Chi Chuan and Kung Fu, and the instruction I'd been receiving placed an emphasis on development of 'root', ie grabbing the ground with your feet. We train with those cloth sole 'Kung Fu shoes', on a polished wood floor at the local VFW hall. Getting a pair of these foot gloves has been awesome, and after reading up on barefoot running, I decided to give running a try again. I think my first few runs were with my regular Asics, but focused on keeping a more rapid cadence, and landing ball of the foot first. I was able to finish a 3 mile run with a 7:30 mile pace, which was quite a surprise. Granted the Tai Chi, Kung Fu, and Crossfit has kept me in good shape, but in addition to the satisfying run time, I had zero knee or back pain, which I had been anticipating.
Now-a-days, when I run, VFFs or not, I run on the balls of my feet. I do notice that my lower calves are sore afterwards, but I guess this is due to never having used them before. I expect that my arches and ankles are being strengthened as well. You do need to take it easy at first so as not to cause a stress injury, but with regular, scaled runs and exercise, your body will adapt and I expect your run time will improve with a reduction in injuries/pain.
Granted, Big Army has now banned VFFs, but the benefit from a barefoot running style can still be had. Merrill, NB, Asics and plenty of other shoe manufacturers make 'Minimalist' running shoes, which provide a minimum of padding, are very light weight, and won't get you dinged for wearing 'fad shoes'.
If something as simple as barefoot running was such an advantage, with the brazillions of dollars and years of research done to shave .001 second off an Olympian's run time, or to give a running back a slight advantage, a gymnast higher jumps, etc, don't you think this woulda been discovered and become standard 30 years ago?
Actually, I recall reading an article about an Olympic marathon runner from Kenya, or some other African nation, who had grown up running literally barefoot. 'Normal' shoes were extremely uncomfortable for him, yet he had never run on asphalt (which was tearing his feet up), but would have to in order to compete in the upcoming Olypmics (1988 I think). Like other humans who have spent their entire lives without shoes, their toes are naturally spread out. Nike made some special shoes for him that had pockets for his two inner toes on each foot, kind of like Japanese 'tabi' but with pockets for two toes instead of just one. You could order a pair of these Nikes for about $3000, as I recall. Our 'modern' shoes are akin to Chinese foot binding, imho.
BTW, have you seen the 'shoes' that gymnasts wear?