I had the opportunity of eating Lugers on Sunday and Wolfgang's on Wednesday, only 3 days apart. Here are my impressions:
The inside of the Lugers steak had more beef flavor. The crusty layer of Lugers, the part that is seared, was more chewy, and thicker, lending I felt a more pleasurable mouth-feeling. Also, with a thicker charred crust, Lugers seemed to have more salty-taste.
Wolfgang's steak was very similar in quality, but the crusty layer was noticeably thinner and more crispy. It almost seemed that they had used a higher temperature with shorter time of cooking, so that a thinner part of the steak was seared, and with a hotter temperature.
Both steaks, on the inside, were as buttery and soft as can be. As an aside, I think using the steak sauce at either place is a shame. These steaks are about as beautiful a taste as you can get, and to add anything to them other than the butter in which they are cooked is like adding color to an Ansel Adams photo.
The Wolfgang's butter sauce seemed to have more pronounced butter flavor, almost a popcorn butter taste to it.
Tomato & onion: Wolfgang's onion seemed a lot more sharp, almost painfully so. Wolfgang had bigger tomatoes, and seemed more ripe (where do they find these things, at the nuclear lab?)
German potatoes: Wolfgang's had a lot of cheese, and was too heavy and greasy for me.
Spinach: I think Lugers had a bit more cream.
Bacon: again, like the steak, Wolfgang's seemed to have more blackened crust to it, that was very charred and crispy. Almost like they didn't clean their frying pan enough.
Wine: Wolfgang's had a longer and better list. I had the margaux at Wolfgang's, which was great. I ordered the '01 pinot noir at Lugers, and they slipped me the '03 instead, which was disappointing.