I honestly think it will be a very good match. Brock vs smaller guys seems to work out as Big vs Small is quite often way better than big vs big. Brock vs Braun was very bad, both times, probably why Braun is not in Seth's spot right now. But Brock vs Finn was downright thrilling because not only did he hang with Brock, he hit his big move at the end and had all The Balor fanbase on the edge of their seats in the crowd (plus as much as people bash Michael Cole, he really sold the late match urgency as well with good emotion). So even though a Mania Brock match has often disappointed in the past, I think this dynamic will work, no matter how much time they get.