Bed slide out/roll out?

Who's got a bed slide, or roll out of any description? I'd like to see them and hear what you like or dislike about it. Something like this:

http://www.cargobed.com/photo-gallery/

Having a shell on I'd like to buy or make one to get easier access to stuff in the bed and also allow better material hauling. Also, if it had sides on it as tall as the wheel wells you could haul 4' wide plywood anytime, and with removable panels to make a deck at wheel well height I could leave it locked in place partially extended and haul lumber 8' - 14' long supported in the middle instead of just the front 6' or 7'.

I'll probably make something, but I need to figure out a good slide and latch design.

 

I used mine with a tonneau cover and it is very useful. And mine has a 1000 lb capacity. I'm only selling mine because I'm installing a flip pac and will have a multi level design in the bed of the truck.

http://www.tacomaworld.com/forum/2n...67230-bed-slide-tacoma-5-bed.html#post6626458