I have driven cars with Alterkations and Magnum componants, so far no personal experience with XV's stuff.

So far I prefer what Alterkations has to offer, it's lightweight yet stout, never had a problem of any kind and the cars I drove with the AK front ends were driven HARD and FAST on various surfaces. One of the cars I drove had the Magnum Force parts and one of the A-arms broke (not while I was driving it) causing major sheet metal damage to the car. To me that was enough to avoid them all together.

I'm sure XV's stuff is as good as anything out there but is it better? Is any difference worth the difference in expense between them and Alterkation? I don't know.

As far as body reinforcements, US Cartools now offers a radiator support and inner fender bracing VERY similar to the XV parts at a substantial difference in cost, plus they make the contoured frame connectors that are all the rage right now, I'd look into what they offer before buying anything else.