I'm running QVR on OS X 10.5.4 (Leopard), and so far—knocking on wood—without a hitch. I'm a writer, and it's been some time that I've been waiting for a little app into which I can quickly dictate passages and thoughts that come to mind while I'm at work. You know how it is, this perfectly worded passage pops into your head but by the time you jut it down, some of it is gone. Maybe I'm too slow a typer, but as far as I'm concerned, QVR is just what I needed. And at the promotional price, it's a pretty decent buy. The only thing I wish wasn't there is the tiny delay between pressing the record button and the time that recording actually commences. It's just a second or two, and while it seems like a long time for my percolating brain, it's really no deal breaker. Thumbs up from me.