It all depends on the weakest link which, in this case, is the small plastic part that lifts the window.
On the OE unit the thickness of the material where the cable threads into it is nowhere near sufficient. It's so thin that it's see through in places.
To rub salt into the wound I also suspect the lube they use may be reacting with the plastic to make it brittle.
As for the cable they used, that thing probably has about 1000lb breaking strength. Talk about a mismatch of materials.
The opposing design allows them the use a smaller cable since it doesn't have to push but I still don't like the use of plastic for that lifter plate when it's such a small part. It just isn't strong enough for this job.
I would repair your existing regulators with the Steiger kit
http://www.steigerperformance.com/ or one of the cheaper copycat versions
http://www.am-autoparts.com/Jeep/Libert ... 03162.html that have a metal bracket and metal attachment to the cable.