I've run my own creative agency for 6 years, now.
Over those years I've tried (and failed) to effectively use countless collaboration tools. All of them lacked something, or required a lengthy tutorial for my client. Nothing was straightforward, there was nowhere to reliably discuss all aspects of a project.
And so, for the past 6 years, I've inflicted serious amounts of brain-strain on both me, and my clients.

QuickReviewer looks like it could change that.
From video review, to high compatibility with all the file-types I could want and (by far the best feature for me) direct website annotations, the software seems to enable intuitive discussion on every aspect of a creative project.
The support is some of the best I've dealt with. It's rare that you get to feel as though software developers are ready to engage in a frank, open conversation about their software. But during my very first contact with them, I felt as though they were listening, and enthusiastic about their clients' ideas.

There are a few UX issues (not deal-breakers at all) that I'd be keen to see improvement on, but having spoken to the support team, I'm confident there will be some great improvements.

For me, this is a no-brainer. It's money very well spent, and I'm looking forward to showing this off to my clients.

Cheers!