The first two are identical in meaning, though I would be inclined to choose the first as it sounds less awkward (no repitition of the word 'other'). Both mean that this way is the only possible way. The third sentence (like this) is slightly different. It does not imply that there is not another way to do whatever, rather none are similar to this one. "This is the only way" would be how I would express this idea. I hoped I helped.