I'll get some pics and upload them this afternoon of my setup.
Generally speaking I really like the Swingcases. If I were planning on using them every day and needed even more storage space, I would have gotten Ramboxes. I just don't like the look of the RamBoxes or the way they take up so much bed space. For me, I carry around some general tools and a couple different hitches for my trailers. They work perfect for that. Plus, they come out in a matter of seconds if you need the full bed to load/haul stuff. I'm very happy with them....the big concern I had was putting small items in the back and not having a bed divider and having them slide up/down the bed while driving. I solved for that using the 2x4's in one of my previous posts....I also just decided to pick up a bedrug bed mat (not the full liner). This will be the perfect combo for me.
As far as blocking the LED bed lights - they definitely do. There is some light that will still shine through but it is limited. However, if you "swing" one of the cases open the entire bed will light up. My plan is to stick an LED light puck on each of my swing cases. They are powered by AAA batteries and only cost a few bucks. For times when I get in the tailgate and need extra light and don't have the tonneau cover open they will work great I think.
This is my $.02 on Swingcases