I've tested this set out, and the thing is, pursuit just doesn't do enough, and people will switch into something that resists Metagross and setup, albeit Pursuit will hurt them, it won't hurt them a lot, and the result of a opponent setting up seems much more dangerous
I used this set in OU as a counter to Latias and it worked great. Pursuit is absolutely necessary as there's no point in switching into Latias and taking a Draco Meteor if it just switches out afterwards. I would recommend slashing Pursuit with Bullet Punch as the first Slash instead of in the last slot as the third. Also I feel as though Stealth Rock is really unneccessary and can usually be left to another poke, but i guess it's fine...
I've tested this out, and because Metagross doesn't really have the ability to lower it's opponents to a significantly low health, BP seems pretty useless, after all, you wouldn't switch it in to take it hit THEN bp, therefore, I suppose Pursuit would be the better option.
I've used an extremely specially defensive Metagross with a Choice Band and it solves the issue of both power and bulk. Maybe try that out? I have no experience with this set, however, and will try to test it when I get the chance.