I have a relatively standard DeWalt rechargeable combo drill/hammer-drill and a Hilti TE-5C type SDS drill/hammer/chipper. Oh wow, the Hilti is HUGELY better. With decent condition bits, the Hilti hammer drills through old, hardened concrete like butter for holes up to about 3/4" diameter. I also used the Hilti for hundreds of large anchor holes (for epoxy rebar connections, anchors, etc) in concrete reinforcement work in an extensive CA earthquake retrofit project and for many hundreds of smaller ~1/4" holes for anchor strips in a large basement remodel in Michigan for smaller tapcon type anchors. Both of these were in old, poured concrete that was very hard. The DeWalt could barely work on either of these projects even with very high bearing force and new carbide-tipped bits. Also, much to my surprise, the DeWalt would leave your ears ringing (ear damage level) even when wearing substantial ear protection. It seemed like a bad joke. In contrast, the Hilti SDS drill was fast, much lower effort, much quieter, less dust, etc.
If you will do a lot of drilling in hard concrete, be sure to get something better suited for that specific job or you may suffer !! I suspect most brands of large SDS and SDS-max hammer drills will work fine and save a huge amount of time and frustration.
