Large files will take much, much longer to verify. Once they reach 100% LW will try to verify them compared to the original hash tree that was downlded the moment you selected that file to downld. For a small file this might only take a few seconds. For a 200+ MB file, it could take quite some time depending on your cpu speed, connection speed, etc.

However, one thing that has been noticed is that when very large files reach about 99% they tend to lose all the multiple sources for some reason. That last 1% & verification seems to take forever sometimes. It might be a problem with hashing of the files. This doesn't always happen but has certainly happened with many large files over a long period of time.