This OVA was really captivating and was a good overview of another future Shinichi must face if things don't go as expected. But if that really happened, I'm betting on that Shinichi would've found a better ending, as in, he would have told Ran a bit earlier of his true identity and maybe even start living up as an elementary school detective, outsmarting the old "Shinichi"! It was also amazing to see how much of an influence Conan was to Ayumi, Mitsuhiko and Genta (they even started a Detective Club in High School) and even to the cold-hearted Haibara who had become a real part of the group in the OVA.
I hope Conan would quit with the stungun sometime soon though.. Lets hope he won't continue confusing the poor Mori Kogoro up til High School!