I've been using coco chips for the last year, year and a half and really like them aside from one recent issue. I started a thread on that yesterday but I won't derail your thread here. Probably similar to eco earth but I've been using Pro Coco chips. Sure a little gets stuck to feeders from time to time but no real issues on that note. Some folks just put down a sheet of paper or cardboard or something under the snake after the snake coils the rat and that seems to help.
Back to your LED options, if you go for the 10mm groove I'd be sure to get the 5050 size LED strip. It will fit super snug in the channel and have no risk of coming loose and exposing the adhesive back of the strip. My 3528 LEDs have been in the cages for a year and a half with zero issues.