Are the lists offered on sites like this worth the price and effort?

Find someone you want to emulate and volunteer your time and efforts to them just for the opportunity to learn the trade. this kind of investment pays of in spades! 

It required a lot more money, time, effort and/or knowledge than they were prepared (or able) to dedicate to wholesaling.

(not counting phone leads)Free, 0 effort, highly motivated seller leads.;)I can't even keep up, so many unopened leads...Telling you all.. you are all missing out!

That said, there’s ways around most everything, it really just depends how much time and effort you’re willing to spend managing the property. 

Did I spend time effort headache trying to skip tracing all the addresses that came back from that silly DMM campaign?

They will and should get paid for their efforts!

Doing PM correctly requires significant effort, technology, and really awesome team members (who command decent wages).

For higher end projects - such as a single family homeowner client vs one of my rental units, I'll typically go through a flooring supplier such as Yonan, where quality is generally higher and colorways are truer to genuine hardwood. 

Their SEO is great, but I will humbly say I have outgrown their (and any) SEO efforts.