is not a bad application, i did actually bought it awhile back, but one thing is don't compare this to any snapping company , it just run from your desktop, it won't grab you some highend domain, unless you are really lucky(but i don't think is gonna happen anyway), so if you want to grab some low end domain, it worth to give it a try
I use it for registering domains that most domainers think isn't worth backordering, but still worth more than reg fee. It's one check per second of course can't compete with the several thousand checks per second of the professional drop companies.
I use Dropsnapper which I was told is the same code as Desktopapi. Dropsanapper was free when it first came out and it does kind of work. You wont get any big ticket names but its real good at catching .info and other lower grade names such as 3 char .com or .biz names. It also comes in handy when you need to bulk register