The good: the spikes were much tougher than I was expecting. The unit works well, IF you put enough weight on it. I started with 8 solid concrete blocks 4x8x16, but I think I will add 8 more to bring the weight up for better penetration on hardpan. Assembly was relatively easy and the price was good. The bad: As others mentioned, grease squirts out of the poor welds around the zerks. I plan to use some brake clean to get rid of the grease, rough up the welds and put on some JB Weld. Another thing that was a bit irritating was that the bolts and nylock nuts holding the spikes on weren't tight and several weren't even put in. I guess they do that for packing, but it seems to be an unnecessary burden on the buyer (me). I spent about an hour putting it together, primarily because of the two issues above. The 3-pt hardware assembled easily enough, but those spikes were a pain. Would I recommend this unit? Yes, definitely. The price point is good and I can work around some of the poor quality issues easily enough. Besides, the assembly is only one time thing anyway. I would have given 5 stars if only the zerks would have sealed around the welds. I can deal with the additional assembly.

While the unit was upside down to bolt up two plugs per disk, I decided to grease each spool, when I pumped grease in one it pushed out a pin hole in the weld that holds the fitting, also five other grease fittings were loose. Then I noticed the support for guide B was not square to the frame causing the guide block to push the spools tight to guide block A leaving a large gap to the spools on the other side of guide block B. I fixed this by adding a thick washer to each bolt on guide block B. When I turned the unit over I noticed one of the welded supports where the back part of the connecting plate attaches is 1/2" out of square, which is noticible but probably won"t cause a problem. Have not used unit, I am waiting for early spring to aerate.