I wouldn't buy links in any of the directories personally, because unless you get loads of them I think they are pretty much useless.
how do you explain the case of dirjournal.com business.com or botw.org? theyre obviously unscathed. and seem to be doing better than they were a year from now botw from what i understand hired a bunch of old dmoz editors recently dirjournals pr shot up in the midst of pr decline from other "big" directories business.com as many of us know was acquired for a very very pretty penny I think. the Dir business may still exist. Given your main focus is to serve your viewers 1st. monetize your service 2nd.
Since they spam and scam, it's obvious they don't like in the first place. Professional companies don't spam, and the directories that do spam, are taking a giant risk.