Power Lift installed 30+ piers on the left side of my house in the summer of 1996. Sometime starting in 2008, I noticed a bulge forming under my carpet in the living room. I suspected one of the piers had punctured through the concrete slab. Knowing we were going to need new foundation work, now on the right side of the house, due to some earth shifting, I waited to start the additional foundation work before to pulling back the carpet to examine the floor buldge. In Aug - Sept of this year, during the new foundation work started (by a different foundation company), I pulled back the carpet and noticed a 9" x 9" concrete plug sticking up out of the slab by about two inches. Power Lift argued that there was no way it could be a failed pier, site unseen, and he attempted to explain the technology used in 1996. They mentioned that to examine the problem any further would be under the terms of the warranty where I would be required me to pay $181/hr for their equipment to be brought up from Van Alstyne, TX, open the hole, rework the pier, and then their travel time back to Van Alstyne, all total $700 - $800. I went to Lowes and rented an electric chisel for $40 and removed the concrete plug myself in about three minutes, it was like a jigsaw puzzle piece and the square concrete plug came out very easily. What I saw was the steel pipe and a simple 3" x 5" steel plate embedded in the bottom of the cement plug, and that's all! Not even a bracket from the steel peer to underneath the foundation slab. The 3" x 5" plate appeared to be there to prevent cement from going into the steel pier when they filled the hole with cement in 1996. Again, I called the Power Lift Sales person, in addition to sending him videos via email. He said he didn't use the computer much, wasn?t all that computer literate, so he did not see the videos I had sent. Without seeing anything, or offering to come out to look, he argued that the foundation shift on the opposite side of the house probably caused the problem. He went on to say if they came out to fix the problem they would use a new technology because they discontinued the technology used in 1996. Hmmm, wonder why? He said the 1996 technology was to push the pier down to resistance against the foundation, allow some lift on the slab by the hydraulic jack against a temporary bracket, fill the hole with dirt, and cap the hole with cement. After the cement hardens, only the steel pipe pier is touching the bottom of the cured cement plug. After hearing that, it was clear to me that the weakest point is where the new concrete joins the original foundation concrete and nothing is really holding up any part of the original foundation. It doesn't take an expert to figure out that enough pressure could pop the concrete plug right out. And, I might add, the concrete they used to fill the hole in 1996 was very lightweight cement and not near the strength or aggregate mix of the original foundation. The sales person said their new technology uses a bracket attached to the steel pier to hold up the foundation. So, in my opinion, there was an failed pier design that has since been replaced with a new pier design and Power Lift was not going to make it right without me paying for it! The shocking part is that I also have several other Power Lift interior peers with this same 1996 design in my house. NOT GOOD AT ALL!! Based on the push-back from Power Lift, and my overall experience, I would never recommend Power Lift to anyone who wants to be treated right. If this would have been an automobile, it would be referred to as a "recall" to fix a bad design and treat their customers? right. As a side note, I selected Structured Foundation Repair for the new foundation work. They did a reasonable job but in my opinion they were focused on getting their crews to complete the job quickly and I personally didn't think the actual lift was well thought out. Structured was about $3k less than my first choice, Hargrave Foundation Repair, who does have an excellent reputation in foundation repair with Angies List and they appeared to me more methodical in their approach to a foundation repair problem. I am an engineer myself, so I can appreciate that.