Cobra hydraulic ramp jacks

Does anyone have a Cobra trailer with a hydraulic ramp jack that does not leak?

My new jack leaked out most of it's fluid after only 3 assemblies of the glider. The fluid is leaking past the small piston. My dealer has offered to replace it under warrantly, but I would like to hear from others who chose the hydraulic jack before I decide if I want to change to the worm drive jack.

Thanks