For true-DC applications, look at the LMH3401 that nctnico used in his 1 GHz+ differential probe. You'll need a split supply (and he also uses a good part for that purpose, the LM27762).
For that matter, there's no religious reason why you couldn't use a 50-ohm MMIC with a split supply. It's not commonly done for a couple of reasons, one being that it complicates grounding and the other being the traditionally-high flicker noise near DC from GaAs and similar materials. Newer parts will still have the first limitation but may do better at the second.