Both are classic gliders. Great examples of a flapped and standard
class ships. Both fly beautifully with the LS-4 being the most
predictable and most comfortable, in my opinion.
Similar to other commenters, I would put my primary emphasis on the
trailer, and secondarily on the condition of the ship.
I have found the trailer to be the most significant issue in the
quality of my soaring day. A marginal trailer results in cut hands,
bumped heads, sore backs, and new dents and dings on the ship. A
great trailer allows easy one person rigging with no personal injuries
and virtually no new damage to the ship.

I purchased an SZD-59 a several years ago that had a Polish copy of a
Cobra trailer. Looked nice. However, all the details of how nuts and
bolts were placed, clearances between wings and trailer sides, how the
elevator mounted in the trailer, how the ramp moved in and out were
sooooooooooo different from my real Cobra trailer with my previous
ship, that I ended up buying a new Cobra trailer for my ship. It made
all the difference in the pleasure of my soaring day. It made all the
difference to me in deciding on a marginal day whether I would go out
to the glider port or not.

Actually, I would base my decision on the trailer first, and the ship
second. Unless, of course, you have the money to pay people to set-up
your ship upon your beckoned call when you want to fly. Then it is
their knuckles, fingers, backs, and scalps that experience the
differences.

Guy Acheson "DDS"