Yeah, just a mat/pad for your knees and something to fix your legs into position will work for "natural" ghr's.
Honestly though, I have had an econo prowler on order for ~3 weeks with no word until I made two attempts. They told me to expect it to ship before the end of this last week and still nothing.
Be prepared for poor customer service if you go through elitefts, which may be the only source for that particular sled
And if you don't think kettleball squat cleans are difficult, I say, step up to the med-ball
- CJ Kim