This is a solid, well-built watch.  Had I purchased it alone I would have loved it.  The problem is that I had ordered two versions at the same time to decide which one I liked better. I got this one and the non-solar, non-atomic, 1987-tech DW-5600E at the same time to compare.

Features the J has that the E doesn't have:

Solar power
Atomic time updates
Multiple alarms & snooze alarm
World time
Auto backlight on when raising your wrist in the dark

Features the E has that the J doesn't have:

Day & date displayed simultaneously on main screen
Countdown timer adjustable to seconds (instead of minutes as on the J model)
Alarm can be set for a specific time, day or month, or any recurring combination of the two
Smaller footprint for both wrist area and height
Time is visible in all screens except alarm set

The bottom line here is that the DW5600-E does the basic task of a timepiece better: it tells you the time, day, and date more easily and with less hassle than the newer model.  There is no selecting the home city, putting your watch at a certain position in the window at night, worrying about charging up the battery, and all the techno-tasks related to a supposedly maintenance-free watch.

The fidelity of setting seconds on the countdown timer is crucial for fitness use (a minute is forever when doing something physically challenging...), or photography (I still develop film and 15 seconds can mean overdevelopment...), or cooking, scientific experiments, etc.

The 5600-E is lighter, smaller, and more comfortable to wear.  The size difference may not seem like a lot on the spec sheet but the difference is tangible in practice.  I like a slim, low profile watch and the 5600-E wins in this area.

It's also about half the price.  The batteries on these things last ten years; if you spend the extra dough on the solar model it will take you the rest of your life to make up the cost difference.  Also, the accuracy of these watches is great - you may get out of synch by about a minute per year, something you can adjust when you switch back & forth from DST.  Neither solar nor atomic is a compelling reason to spend twice the money.

New in this case doesn't mean better.  Unless you're a frequent traveler with world time being a prime consideration, or have a need for four daily alarms, the older 5600-E does the job of telling time easier and more affordably.

EDIT:

I've evloved my opinion.  I think pretty much any 5600 (or 5000) model is great.  I got my atomic models to synch just fine, I just have to do it at night and facing west.  Really can't go wrong with any of these.