I downloaded the trial edition and it found quite a few subtle issues in some of my unit test code. Nothing too serious, but stuff that other tools have missed. The run-time overhead doesn’t appear to be that great, my server tests still run at a reasonable speed and nothing fails because of the instrumentation. My virus checker (Bitdefender) hates the tool, probably due to the code injection and whatever that’s required. The developer is easy to talk to and interesting in dealing with any issues that you have.
The price is a little steep, but I got a decent discount for being a reader of Bartlomiej’s blog and that helped. I’m not sure I would have purchased otherwise. At the discounted price it’s a useful addition to my toolbox.