I got my Dragging Sled last week and I'm loving it so far. My sled weighs 60 lbs., whereas the EFS one is only 35. The most amount of weight I have put on it so far has been 45 lbs., and I definitely felt that.
I am pulling it along a straight section of rubber mats used for sprinting at my gym. Maybe 70-80 feet long.
I pull it very strictly. I don't run with the sled and I try to use as little momentum as possible. I power-walk down the track with the strap attached at the back (for hip extension) and at the front (for hip flexion). My hands are on my belt for stability and my midsection is tight the whole way through.
I would like to know the typical poundages and distances that people use their sleds for so that I can get a sense of what I should work up to. Please post your weight as well, since it obviously makes a big difference in how much you can pull. I'm a tall, skinny guy who trains as a bodybuilder so pulling heavy things is a fine art for me.
Lastly, I love my sled so much that I can't make a thread about it without posting the ebay link where I bought it for only $110. That's $90 less than the EFS, and it even came with a band attachment. Sold by some guy in Arizona.