Updated: I'm right at two years with mine.  I purchased it with a specific use in mind.  I swim regularly.  Based on the feedback of other swimmers, waterproofness of digital watches is hit or miss with most staying water-tight.  That is, until the battery has been replaced.  After that, it's often a "miss".  So, I bought a watch that shouldn't need a battery replacement during its expected lifetime - the WS-220-1A.

I love the watch.  As someone else said, it resembles a G-Shock.  Love the looks, the accuracy (it gains 3-4 seconds per month), the features and the improbability of ever having to replace the rechargeable battery.  I initially topped off the battery by leaving it on my windowsill in direct sunlight for a day and it's never indicated less than fully charged since.

It's become my daily wear casual watch.  5 stars.

Addendum: My family own's six Casio solar watches.  We love them but we understand them.

1. A solar watch uses the energy of ultraviolet light to charge a a lithium based rechargeable battery.  Many who don't know that solar watches charge using the ultraviolet portion of the spectrum often try to use light sources that won't work (desk lamps for example) and are disappointed.  Direct sunlight has copious amounts of ultraviolet; fluorescent based light has a little; incandescent light has effectively none.
Q: Why didn't Casio design mine to use visible light so I can use my desk lamp?
A: You don't want to know. (It has to do with usable voltage and the physics of photon capture using doped semiconductors.)

2. The capacity of a typical solar cell watch battery is huge compared to the watch circuit's daily power requirement.  Most should give his/her solar watch a big charge once or twice a year then not worry about what it gets daily.  We set ours in direct sunlight for most of a day several times a year then treat them like any other watch the other 363 days.  If your watch gets little charge boosts from daily wear, great.  If not, it's no big deal.  According to Casio, a FULLY charged battery in this watch will run it for about 11 months with ZERO exposure to ultraviolet.  But a FULL charge takes time.  For a nearly exhausted battery, that's 31 hours of direct sunlight, 155 hours of direct through a window, ... (see manual).  But your battery should never be nearly exhausted.  Ours all arrived with what I'd estimate to be 70 or 80 percent charge and needed a day, in one case two days, on a sunlit windowsill to reach full charge.  I repeat, after the initial charge, every one of our solar Casios has remained in the highest charge state with NO special treatment save two days a year on a sunlit windowsill.

3. The most common loss of water tightness in watches is a result of battery replacement.  Because the battery in a solar watch should last twelve to fifteen years, you are significantly less likely to suffer water intrusion problems with a solar than with other watches near it's price.

addendum:
4. The bezel is significantly raised at the top, bottom and both sides which provides quite a bit of protection to the acrylic crystal.  Many of the lower priced watches sold on Amazon are falsely listed as having mineral crystals. (Mineral crystal is much more scratch resistant than is acrylic.)  Don't believe such claims for watches that sell below $60 or so; with a couple of exceptions, all have acrylic crystals.  At just past the two year mark, my crystal has one extremely small scratch.