A feature that you can quickly notice on modern Russian aircraft is the complicated nose pitot tube. Although AMK made a valiant effort in molding the MiG-31 pitot tube with its four separate vanes, the limits of the injection molding process come into play.
Notable is the superb re-sealable packaging that Master Model uses that makes the parts easy to review and then stuff back into the package securely until final assembly. The resin vane section is secured in a high density foam block that is backed with some sort of adhesive tape to minimize the resin vanes from being moved around, or crushed for that matter. You will want to be careful handling the metal and resin parts as their small size makes them an easy sacrifice to the carpet monster. The resin part is especially easy to break one or more of the vanes in handling (as I had happen on a previous Master pitot set), so be sure to handle with care.