Making items like the MBC and other inferno dyna phats that have insane market values shouldn't be added as inferno quest items.
1. It screws over everybody who has one of these weapons currently, as everybody and their brother can get the item for free that some have paid hundreds of millions of credits for.
2. Making them freely available to whoever wants them gives, in the case of the MBC, a fairly uber PvM to every profession. This would kill the diversity in the game for most professions where this would be the best endame weapon option.
3. If the items are absolutely required in the storyline, then a much better version of the original non-nodrop weapon should be added to prevent the listed problems but still be able to be added in the storyline.