I have had few months to use the Zoom H4N Pro along with my Tascam DR-40 since my earlier review. There are a few features that might make you consider the Zoom instead.

• Zoom H4N Pro has a 3.5mm (⅛ inch) stereo input on the built-in mics that lets you add two more external mics. Tascam DR-40 is strictly two external mics.
• The noise level on the H4N Pro is slightly lower
• The H4N Pro can act as an USB interface, that is, it can record directly to the computer from an external mic. This is of limited utility in my opinion. The computer is always a less reliable recording device than the dedicated device. Still it's there if you need it.
• The H4N Pro comes with a plastic case that keeps it from getting dinged in a bag