A solid-state drive array keeps your video edits and backups fast enough that you likely won't need to replace the unit for five years. Buying a high-capacity unit now means you stop juggling cheap thumb drives that eventually fail or run out of space when you are in the middle of a project.
New tech usually drops in the fall, which is when retailers slash prices on last year's inventory to clear their shelves. You can grab a top-tier model for less and use the Citi Simplicity® Credit Card (Citi) to manage the bill over time.
This 18-month window is a tool for breathing room, but it is not a discount on the total price of the drive. If you still have a balance when the 18 months end, the standard interest rate will apply to whatever amount is left on the card.