Do the math before you make a decision -- free financing for 60 months --that's about $13 more per month. Not a great jump, but still it adds up to $800 in the long run. The fact that the financing is interest free keeps the cost of this machine in a very reasonable range.
How long do you normally go between machines? If it is a long time, the upgrade might be easy to justify. If only a little longer than the time you are financing it for, perhaps the less expensive model, so you have the $800 not spent to get started on the next new machine....