I have watched this edit. My memory of the original is a bit fuzzy, but I think a few scenes have been cut down (Starscream's coronation specifically). Probably not enough to be significant.
As to the new score, I'm iffy. Some scenes worked well, others not so much. Part of the problem with using Duel for the Megatron/Optimus fight is that it's over too quickly. For good or ill, I hear that music and expect a long and exciting battle. I expected new music during the battle for Autobot City, so to have the original was jarring. I didn't mind that you kept Dare, but it is out of place, being the only section where the real music is left in place. To not have The Touch threw me for a loop since we'd kept Dare, and those are the two Stan Bush songs. I loved the podrace music in place of Instruments of Destruction.
I still have my BetaMax tape of this movie. There were places where I could tell that lines were missing. I could half hear some of them due to the rebuilt sound. Other times the audio cuts seemed hard, and there were a few places where the sound just stopped at the end of a scene before the sound far the next picked up.
This was an interesting experience. Based on the trailer, I thought I would enjoy it more than I did. I will show it to a friend, as Transformers and Star Wars are two of his favorite properties, but I don't think I'll burn a disc of it. I know an incredible amount of work went into this, but the end product just wasn't satisfying enough.