
The software does a good job of removing bogus emails or correcting basic syntax errors within email addresses. Review collected by and hosted on G2.com.
There are a few issues I've come across some of which could be resolved some are a little trickier. The biggest issue is verifying yahoo domains as the domain gets blocked after about the 3rd or 4th yahoo email. The same thing happens to other domains after a longer period of time, but that problem could be fixed with domain specific rate limiting or pre-processing before using the software. Review collected by and hosted on G2.com.