Yes, this item works well.  But yes, it takes some RF and electronics knowledge to make it work right.  For me, I have verizon cell phones operating in the 800MHZ cell band in my area.  In my house we had zero to 1 bar and could make calls but they were frequently dropped or cut in and out.  We could walk down the block and the signal was better.  Our house sits in a depression and most of the cell signal was going over the top of our house.