You are buying this machine to pull real cafe-quality shots at home for the next ten years, which means you want a heavy-duty brass group head and a dual boiler rather than a plastic toy you will replace in eighteen months. Paying $900 hurts less when you wait for the late summer clearance cycle, which is when retailers slash prices on last year's models to make room for autumn inventory.
The older version often has the exact same internals as the newly announced machine, just with a different color panel or a minor badge change. Let the people who need the absolute newest box pay the full retail price while you grab the proven model on sale.
That intro window is a hard deadline, not free money, so make sure the $900 balance is gone before the 15 months run out or you will get hit with all the deferred interest.