I just purchased the program and even though that I love the concept, I'm finding it pretty hard to scrub back and forward in an easy way. I
As Matt pointed out, scrubbing performance will vary based on a variety of factors. We are currently revamping InqScribe’s media engine, so hopefully you can expect some general performance improvements on the next release.
You can read more about our future plans here: http://blogs.inquirium.net/inqscribe/2014/03/retiring-quicktime/
AdminMatt Brown (Partner, InqScribe) commented
InqScribe does support scrubbing, but performance might vary based on the particular file format you're using, which default media engine InqScribe is using, the size of the media file, and your machine's performance. We're always glad to help sort through these issues via our support desk. Feel free to contact us there at firstname.lastname@example.org.