As long as it's LSD, you're fine. If your installer can read, he really can't mess it up. LSD provides detailed instructions, and has terrific resources on their website. My installer was able to look on their website the night before I showed up with the kit to map out how he was going to do it.
LSD is the ONLY crash tested kit. It is the only one that gives you the quality and reliability that they do. Look at this hinge:
It's one gauge steel. I think it may be stronger than my Magnum's frame! LOL
I saw a gorgeous 300C with a different kit at one of our local meets and many of us commented on how it was put together. if you leaned on his fender, it would buckle in. The wiring was sloppy too. LSD's wiring is clean and tucked away nicely.
I did a lot of research on various kits and discovered LSD was the only way to go. After talking with several dealers, ALL of them (even ones who did not carry LSD) suggested going the LSD route.
Here is a nice graph to give a side by side comparo on the most well known brands: