I used one a few years ago.
I think I got one for $75, not including the tray & arm price. I never needed the fiber optic cable. it slaved off my camera's internal flash pretty well without the cable.
is it any good? that is very subjective.
It doesn't have a lot of power or angle of coverage, but I thought it was a good value for the money. It was very small and light, great for beach diving, climbing down cliffs, rocks, etc. worked decent for macro photography. It allowed me to significantly reduce backscatter on my shots.
of course, you really can't compare it to more expensive strobes like the ike Ds-51, S&S Ys-90, or inon D-2000, those are more expensive, but much better strobes.
so if you spend more, you get more.
hope this helps
scott