I ran the CALMINI LSD up front and a modified stock LSD in the rear for a while, really liked this combo The additional traction to both axles was more cost effective & beneficial than just adding a rear locker to me. Steering will be a bit tighter especially at standstills with a front LSD and it takes a while for a new unit to loosen up.

Of course you will be putting more stress on the steering system, CV joints, hubs, etc and your chances of breaking something increase. At the minimum you should consider a steering system replacement with a front LSD or locker and manual hubs are also recommended for both. Also going with the fuseable hub rings like LAX runs is also cheap insurance against certain types of CV breakage.

No LSD no matter how tight is near a full locker IMO but there a good comprise and helpful in certain situations.

As far as used one…more than likely you will need to rebuild it since all the ones I've seen have been pretty much worn out and the short side axle will need the retainer pressed in for it to work.