I dug footing for my cabin and hit two major granite rocks. I purchased a $700 dollar jack hammer and it didn't even make a dent. Backhoe with rock hammer would have been $1,700 a day. I bought a Bauer hammer drill ( get SDS max), landscape lever, and a small paint mixer for around $300. This product has absolutely impressed me. Just don't take short cuts. Drill deep and buy two bits. 1" works great. I wish I would have found this years ago when I built my house.

the product worked pretty well for removing concrete stairs. Broke off in pieces that were manageable to haul away. The only drawback to the product is very few people will have the needed sds max rotary hammer drill or the 1 1/2 inch diameter sds max drill bit needed to drill the recommended hole size. I bought the drill at harbor freight for $179.00 and the Bosch SDS max bit at Lowes for $109.00. You have to drill quite a few holes at the recommended spacing of 12 inches apart if you want the concrete to break off in pieces that can be easily lifted and hauled away. It took me a couple of hours to drill the holes but the payoff was being able to walk away and come back the next morning to remove the pieces that had cracked between the holes.

Worked extremely well!! I had a hard time finding reviews with only partially exposed rock. My rock doesn't seem to have a bottom to it but I only needed to remove the top 12" at the rocks highest elevation. I used 1 1/4" bit and also a 1" bit. The larger holes produced larger cracks. The larger bit does take longer to drill. I would if I used a 3/4" bit first then the 1 1/4" after that seems to make the process go faster. Tried enlarging the 1" holes with the 1 1/4" bit and the larger bit kept getting stuck. There is a learning curve with drilling, you will need a pipe wrench to unstick your bits. Bought a roto hammer drill at HF for $125; that would have been a 2 day rental at HD.

Came very quickly, can't wait to try it out!!!

*UPDATE* I think it works fantastic, I was digging a 3" deep trench in NH and hit 3 big granite boulders that my little tractor backhoe couldn't even find the edges of. They impinged about 2' into my trench.in height I borrowed a big rock hammer drill from work and found an 1.5" rock drill bit and just using intuition drilled at angles to what I thought would shear the tops off of the rocks, plus holes vertically down to break up the rock as well. Mixed up the Dexpan right where i was working and poured her in. I would go out every few hours and stare at the boulders and of course nothing happened. after 2 days walked out and they were all cracked, Took a crowbar and pried the pieces apart and got them out of the hole no problem. The granite fractured brittle and had a dense "knot" of stone in one spot that it fractured around, so on one of them I had to drill a coupe of more holes and bust that part up, but pretty simple. I drilled and hammered the tops off of some granite in my lawn a couple f years ago to make mowing easier I wish i had this stuff then!

Made the concrete demolition job a lot easier.