Weby - For SOX (Sarbanes-Oxley) it should be the easiest sell there could possibly be. For HIPAA it should be too. Same for the government. Personally, I would think same for the banks too.
An enterprise-wide sale... Any enterprise-wide sale requires multi-organization cooperation and buy-in. This takes some time. The other fight would be if Wave and its partners are fighting against other major behemouths (i.e. Cisco). If a firewall isn't needed then there's also a retirement (future-state) plan that must be architected, and implemented over time. So there's lots of reasons why this will take some time too. IT doesn't hurt to have a few bucks for educating (usually via entertaining) the executives either.
So there is a value proposition, and there are some hurdles to getting wide-spread enterprise adoption ~ but the purchase itself should be a no-brainer to all.
That's why I'm invested! :-)