NitroFlare does still work, but only on certain configurations of operating system and browser.
It is utterly useless on any Mac running Safari: NitroFlare is infested with "Virus Warning" scams and they instantly lock up Safari before you can click out of them (ditto Uploaded). Safari opens the malware windows too quickly and then chokes on them. Since the only way out is to force quit Safari, you'll never make it thru all the BS adware screens NitroFlare requires before you get to actually download anything (and if you do, expect 10 hours to download a typical 700mb file). DataFile has been completely ridiculous for the past two years: they were OK until they started with the 3 hour queue before you can even click anything, then when you do the download process takes 12 hours (longer than NitroFlare).
I have a separate old Mac Mini specifically dedicated to porn and other downloads. It runs OS 10.5.8 and FireFox 16.0.2. This combo is slow to load most malware screens, giving me a chance to close them before they lock up the browser. If it does let a lockup screen thru, I can usually work around it by minimizing it. If you prefer Macs, and do a lot of downloading, I suggest buying an old one to use just for downloading (as I have done). Newer Macs with newer OS and browser are too vulnerable to the annoying malware screen lockup scams.
Occasionally I'll use a Windows 7 laptop with Internet Explorer, which has an expired Norton security suite pre-installed. Despite being expired since 2012, Norton still blocks every malware lockscreen: I never see them, it just tells me it blocked them with a little alert box. So this may be another workaround: get an old Windows 7 box that has pre-installed Norton (mine is a GateWay inherited from a friend who upgraded). This laptop has never once failed to reach the final dowload button on any annoying host site. The only problem I've ever had is it gets misdirected by FileSpace: if I choose "download" instead of "stream" it defaults to "stream" and refuses to download. So I need the Mac for FileSpace.
I don't understand the logic behind most of these host sites being infested with screen lockup scams anyway? Do they get paid a lot of money by the scammers? Don't they realize no one will bother with them if they constantly lock up our browsers? Or do they think we're so stupid as to sign up for their pay services if they annoy us enough with lockups? The nonsense with the 10 and 12 hour download speeds also needs to go- I flatly refuse to EVER sign up for a service that tries to force the issue with ultra-slow free downloads. Free isn't "free" if it ties up my computer for an entire working day: those hosts get crossed off my personal list. I've paid periodically for Filesmonster, Rapidgator and Uploaded because their "free" speed was slow enough to encourage me, but not so slow that they were being obvious pricks about it.
NitroFlare and DataFile can roast in hell: I have no use for abusive host sites (slow as death download speed is one thing, but adding malware lockup screens on top of that is simply disgusting). A" free" host should be at least tolerable in free mode: slow enough to encourage subscribing, but not so slow as to be unusable. And no browser lockup malware: thats just unbelievably stupid for them to get involved with.