Yes we use all polypipe. I don't know of anyone still using the hard gated pipe around here. Yes we just try to let the water run through. Most all of mine has the holes sized for the runs so it takes 12 hours. We used the computer program from Delta Pipe to figure our hole sizes this year even though from years of trail and error we had a pretty good idea of what we needed. It did let us go back to using a 12" pipe on most of ours instead of 15" so we had some savings there.