Today, players like Gata Kamsky and Magnus Carlsen frequently employ the London System, and it has become a staple in the repertoires of many other grandmasters and non-grandmasters alike. The system’s various move orders and the resulting transpositions make it unique, adding a layer of complexity not as prevalent in other openings.
My personal experience with the London System has been mixed. After losing a game to Grandmaster Volkov in the Rilton Cup, I initially decided that the resulting positions were not to my liking. However, in 2019, I revisited the London System during a game in a World Senior tournament and played exceptionally well. Like any opening, it can lead to both good and bad games, but the London System has undeniably become a significant part of 1.d4 theory.