BMD is designed like a piece of crap. It's WAY too manual to be useful. No way to auto-detect what kind of bookmarking script a domain is running??? Plus the handling of bookmarking sites is just terrible. You can't even delete any of them after they get added... and you waste a lot of time submitting to dead sites that you couldn't make accounts for. I had to write my own script to handle cleaning up the sites, but it should have been built in.
Plus the non-recaptcha captchas can be automatically cracked. But instead you have to type them in yourself. And there's not even decaptcha support... none of these are hard to build in, but they would make life MUCH easier.
If you have any programming experience, I'd suggest writing your own auto-submission script. A simple working script doesn't much code... at all, you gain useful experience, and you save $75.
Otherwise, if you're willing to spend a shitload of time setting up things that should be automated, go ahead. At least the bookmarking and pinging aspects are automated...
But maybe we'll see some major improvements in BMD 5.