Well, there have been plenty of discussions just about everywhere about standard or reverse shackles, and there are positives and negatives to both.
In a reverse shackle setup, with the shackle in the rear, it will give a better ride, as the axle will be able to move with the bumps, if you hit a bump or are traveling on washboard roads, it will be allowed to move rewards, away from the impact. The negatives to running them in the rear would be nose diving when you hit the brakes, possible damage resulting from hitting a large bump and having the tire move back into the wheelwell, or even driveline or transfercase damage if you do not pay close attention to driveline length. On steep hill climbs, if you lose traction with the rear axle, the front will try to "walk" out from under the vehicle, resulting in driveline seperation or even bent springs. On steep downhills, the shackles could unload and allow the vehicle to tip forwards.
With the shackle in the front, you don't have any of the previous mentioned dangers, as everything is pivoting from the same end. This means you won't have the danger of driveline seperation, tire and fender damage, nose diving, and some say it gives you a little better traction, as the tire rotation is pushing down and loading the shackle, rather than up and loading the shackle. SO basically, the trade off is either good ride, or damaged components, from my point of view anyways.
Long story short, I chose to run the shackles in the front, for all the above reasons, beings this is a trail rig, not a Cadilac.