In 1991, LEGO released 2 Space M-Tron sets, all of these sets have been retired. For that year, the total price of all retail sets cost $3, today those sets are valued around $246, a growth of 8131%.
Most valuable 1991 LEGO Space M-Tron set
1478 Mobile Satellite Up-Link $206.11
Largest 1991 LEGO Space M-Tron set
6862 Secret Space Voyager 254 pieces
Theme / Subtheme Space / M-Tron
Year 1991
Pieces / Minifigs 31 / 1
Availability Retired
1478 LEGO M-Tron Mobile Satellite Up-Link
Retail $2.99
Value $206.11
Growth  +6793.3%
Annual growth 11.1%
Theme / Subtheme Space / M-Tron
Year 1991
Pieces 254
Availability Retired
6862 LEGO M-Tron Secret Space Voyager
promotional
Value $40.00
Annual growth 1.6%