Just got finished with a rollcage I built for my Slash. It is intended to be run without a body and hopefully will keep me from going through a body every couple of sessions.
I really like my JConcepts tray cover and it keeps all of the crap out of the tray. None of the current products on the market let you use the tray cover, or offer easy access for battery changes. I hinged this one in the back so it allows me to still do both.
After a couple of light runs, (havent really bashed it yet), it seems to really strengthen and support the chassis. The whole thing, with the mounting brackets included, weighs less than a pound and is barely noticeable in terms of speed and handling. (I am not concerned with track times) In fact, the added weight and strength make the truck feel more aggressive for off-roading.
Just thought I would post it because I would like to hear what the people who know and own Slashes think......