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You'll be fine with the 1440. The cases in which you'll see a visual difference are few and far between, and even then they're so minute you'd never notice unless you're looking for it. Epson's stock advice for "help, my paper's getting soggy" is "cut the resolution back," so clearly they don't think it's a huge deal either.
If you were using a Canon I'd definitely advise making a stack of test prints (the differences between resolutions are pronounced and occasionally horrifying on the imagePROGRAF family), but you'd be hard pressed to end up offended by the difference on an Epson. If you've got some paper and ink to blow, making a couple test prints as Cphoto1954 suggests is still an informative exercise.