I have a CBI bumper and went with a full set of CBI skids in aluminum. I went back and forth between all steel, steel front, or all aluminum. Ultimately I went with all aluminum for the weight savings and my primary use case which is just getting out to remote places and not rock crawling. They've held up just fine, but I've never seriously dragged them over anything. There's an oil drain panel, but it's pretty easy to drop the whole front skid and that's what I usually do. The front skid doesn't have the reinforced center section that lines up with the front jack point. I've nonetheless jacked up the front of the truck using the front skid to slide in jack stands. That didn't bend anything. The rear skid has one very difficult to reach bolt. I once got myself into a pickle when I used a ratcheting box wrench to tighten up a nut. The CBI front skid is one of the wider skids out there and extends past the KDSS shock. I installed a front KDSS space with my lift to pre-empt any KDSS lean. It didn't work and I still got leaning. The front KDSS spacer extended the KDSS shock which caused it to run into the backside of the skid. I've since taken out the front KDSS spacer. As an aside, I haven't had any noticeable leaning lately. I didn't mess with the KDSS valves or do anything to try and fix so I'm wondering if it just took some time and driving to get the fluid equalized. Fingers crossed.
I don't know how other skids work, but the CBI rear skid required removing two pieces of diagonal bracing. I was kinda concerned about that. I emailed CBI and according to them, the strength of their skid more than makes up for the removal of the bracing.