I'm in California, so anchoring vertical receiver compressors is a must. I know a lot of folks utilize hockey pucks under the mounting feet, but they are too hard to be an effective vibration isolator. I prefer rubber vibration pads designed for that purpose.
An important aspect that is mentioned in most manufacturers operator's manuals is the importance of shimming where necessary to insure that all 3 or 4 mounting points are even.
I use 1/2" wedge bolts with nylock nuts as it is recommended to back the nut off after contacting the foot so as not induce any stress on the receiver mounting points.
When drilling the mounting holes, I prefer to drill completely through the slab so in the event the compressor is removed, you can drive the wedge bolt below the surface and patch the holes.
You need to be absolutely positive that you have your heating lines marked before drilling.