Transaero proved itself as a company I would not want to travel with. UN 302 (TLV - DMO) was delayed due to UN's 737 major malfunction. It took more than 32 hours to get another UN a/c to TLV , the company , however, refused to send pax on another company's flight. Disturbed passengers tried to riot (!) in the airport , while blocking the entrance to the jetway for boarding LH flight to FRA. Airport police quickly vacated those pax, no arrests were made.
UN has a history of technical disorders on its 737 fleet. My guess is that that(together with high demand for TLV-DMO/SVO route) made UN to send their newly acquired 742s to TLV. (great livery btw).