MBUS is for emergency situations where you're forced into a building and thus CQB is necessary. Take off the Bravo/HAMR, and you can use the straightforward ironsights for ranges under 25 meters.
Reason for the extra Bravo/HAMR: Because 40mm drops hard, the gun is raised in a way that blocks your view of the target when zeroing at 50 & 100 meters like this – https://i.imgur.com/kG1E1cd.png (You can zero your weapon by pressing PgUp/PgDn) However, if you use Bravo4 or HAMR under the red dot, you can get around this issue like so – https://i.imgur.com/XPp7eDt.png
M381/M441 are extremely expensive on flea market at around 100k per round, while peacekeeper only sells 1 round per reset. You don't need these no-brain rounds for long range shooting.
M386/M406 are long range rounds, therefore most people don't even bother using them. This is advantageous for us, because the market price often tanks below 15k rubles like this – https://i.imgur.com/Z02U0EC.png
M433 and M576 is inferior & useless, so disregard them. We'll be primarily using M386 & M406, at a cheap price of under 20k ruble per shot.
Optimally, you'd develop a gut feeling of ranges in tarkov, which enables you to adjust zeroing among 25/50/100 appropriately.