It's a whole new movie, and in its own way it's a masterpiece; one of the best comic book movies ever made. It delivers justice for Zack, the fans fought for this and the characters butchered by the theatrical cut.
Each and every character breathes and shines in this one. Steppenwolf is no longer just another side-kick villain. Darkseid is perfect in every second of screen presence he has. Music is much better than the botched-up cut. Cinematography is also on another level. The Snyder cut connects with the audience in a far superior way in every aspect.
Well, the runtime could have been shorter, pacing could have been better, VFX/CGI may have improved further, but if we take into account the whole journey this cut has gone through to finally come into existence............it's an epic rendition!