At those numbers, it could easily be seen as a price cut.

($1500/$30) = 50 months / 12 ~= 4.16 years. More than 4 years to break even, not including time-value of money.

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Edit: The actual prices are probably closer to the actual turnover for people upgrading Photoshop.

($1500/$50) = 30 months / 12 = 2.5 years.

($1500/$75) = 20 months / 12 ~= 1.67 years.