I vote locker after the sliders. I don't care how slow you go, if you can't get traction you aren't going anywhere.

The locker can also help you to move more slowly through terrain, because you don't always need momentum to get you through.

The gears are a definate advantage, especially with the manual trans. With an auto, I wouldn't hesitate to get the locker first though. In the end you want both.

Of course after a couple of years even the terra lows aren't low enough <img src="/forums/images/graemlins/wink.gif" alt="" />

EDIT: Something to consider with rear locker when choosing, is that an auto locker (Detroit, lockright, etc) will tend to cause the vehicle to slide around more in slippery situations, such as side hilling in mud, muddy hills or icey roads. You learn to deal with it, but it something to consider when choosing.

<img src="/forums/images/graemlins/kewl.gif" alt="" />
Mike