The JLA get stomped. Thor and Surfer would stalemate the heavy hitters like Superman/Wonder Woman/Green Lantern.
Who does that leave to take on the Void? Aquaman, the Flash and the Martian Manhunter give or take Green Lantern? Not much competition there.
It should be the JLA/Thor/Surfer vs. the Sentry for a more realistic fight and even then they could very well lose the majority unless Thor gets lucky or some serious uber team work is put into play.
At full power, the Void was intended to be closer to a being like Galactus or other cosmic anomalies rather than a herald. Whether that was put into practice more often is another story but it was implied/shown often enough for him to get the clear win. And by implied, I mean flat out stated that he was beyond the likes of herald level beings and they are absolutely hopeless to stop the Void.
Even under Bendis during Siege, the Void's power level was ridiculous relative to beings under Bendis. Look at the team it took to stalemate/fight everyone from Nul and Thanos to Galactus. The line up and odds facing Sentry get a lot more impressive in the face of how shitty Bendis is with respecting tier levels. This is a guy who would let (And I am dead serious here) Luke Cage tossing Wolverine affect the Anti-Monitor or Galactus. The worse thing Darkseid could ever do is invade Marvel Earth when Bendis is in charge of an Avengers book.