Opening Twilight Masquerade 3 Pack Blister [Snorlax] returns about $13.42 in card value against its $45.32 price — roughly $0.30 back per dollar spent. On current prices, you lose money on average by opening it.
See every card and pull rate in Twilight Masquerade
How expected value is calculated — card value only, from published pull rates and daily market prices.